Obesity

I had to comment on this. The reporting in the US is disgustingly self-serving and/or pandering.

Disclaimer: The following text is at the end of this as well.
Obesity is a charged word. Some people hear it and think bad things about someone. Others hear it and get angry because we as a society are not "fat-accepting." Whatever your weight is, you are beautiful. You are you. Accept yourself for what you are today. You may wish to make physical changes, but first, love yourself.

A recent article that appeared in newspapers and magazines throughout the country had the following headlines: "Fit and fat: US study shows it's possible." and "Study: Fat people not necessarily heart risks." The real headline should have been "Study shows strongly positive correlation between large weight to height ratio and symptoms of metabolic syndrome." Of course since excess fat accumulation is also a symptom of metabolic syndrome, this would not have been a surprise to anyone.

From the headlines you would think that the article will say that obesity is OK, and the article kind of does say that. It emphasizes that not all people defined as obese have metabolic problems and many people defined as "normal weight" have metabolic problems.
This table shows what the study actually describes. Obese people have a much higher probability of cardiometabolic abnormalities than lighter weight people. Even if you are light weight, you still have a chance of cardiometabolic problems. The articles do not discuss causality or mitigation techniques, just correlations and associations. The New York Times article was more even-handed than most.

If you read nothing else in this post, I hope you understand how misleading the reporting is on the story.

The articles do not tell the whole tale

There are some interesting potential issues not brought up in the articles. The first is the definition of obesity. Typically, researchers apply the obese label to anybody with more than 30 BMI.

BMI = [ (weight in lbs) / (height in inches)^2 ] * 703

Notice there is no mention of fat at all in the equation.

Walter Payton, one of the great running backs in NFL history was 5'10" and 210 lbs. His BMI was 30.1. By this definition he was obese. He was in no way fat. His body fat must have been 10% at that weight. I am no Walter Payton, nor are you, but this points out the flaw in BMI, it makes some gross assumptions about body composition that may not be true for any individual. So of the 31% of "obese" people who had good metabolic indicators, how many were strong athletes?

On the other send of the spectrum are the skinny fat people. They have a low BMI, but they work really hard with cardio and diet. They have probably had weight problems in the past and have experienced some yo-yo dieting. Their arms and legs are skinny, but maybe they have a bit of a gut. These people can easily have body fat percentage greater than 25%, yet they count in here as skinny. I would estimate that there are more people in this category than fit people in the obese category. There are probably lots of both in the overweight category.

A better metric mitght be the FMI or Fat Mass Index. It is very similar to BMI and is in fact a component of it.

Remember BMI is

BMI = [ (weight in lbs) / (height in inches)^2 ] * 703

It can be broken down to

BMI = [ (lean weight in lbs + fat weight) / (height in inches)^2 ] * 703
= [ lean weight in lbs / (height in inches)^2 + fat weight / (height in inches)^2 ] * 703

Removing the lean weight part, we are left with the Fat Mass Index (FMI or BFMI)
FMI = [ fat weight / (height in inches)^2 ] * 703

Removing the fat weight from the BMI equation gives the Fat Free Mass Index (FFMI)
FFMI = [ (lean weight in lbs / (height in inches)^2 ] * 703
Adjusted FFMI = [ (lean weight in lbs / (height in inches)^2 ] * 703 + 6.0 * ( Height (m) - 1.8 )

According to this link (which also has an FFMI calculator), an upper limit FFMI for a steroid-free person is about 25. This abstract addresses the variations in FMI and FFMI associatedf with given BMIs. Here's another one.

Second, there were no indicators of age in the articles. What factor would age play in cardiovascular and metabolic risk. Does it matter how long a person has been overfat? Wouldn't a person become more insulin resistant over time. How many of the healthy overweight and obese people in the study were still young and have not had time to build up insulin resistance?

Finally, the measures used were blood pressure, cholesterol, triglycerides, and blood sugar. It did not measure actual mortality, only factors that correlate with problems. We don't know if heavier people would have lower mortality from other causes.

So I believe we should define obese in terms of body fat, not BMI. It's a continuum really and different people carry fat differently and our measurement techniques for body fat are inaccurate, so I will define obesity as follows: If you are a male and have more than 20% body fat or a female and have more than 25% body fat you probably have some health issues causing fat accumulation.

If you don't have access to a reliable body fat measuring device, consider the following. If you have a BMI over 30 and think that maybe you are not actually obese, one way to measure it is through strength. If you are a male, drop and do 25 high quality push-ups. if you can't pretty easily, you probably have too much fat.

So What? Is fat bad?

I'm not sure really. Excess fat is often a symptom of some underlying physical problems, although it may not be bad in and of itself.

We are taught from an early age that "beauty is only skin deep" and "don't judge a book by its cover." That doesn't change our visceral response to obesity.

Limits options: One of the ten emotional needs in a marriage according to Stephen Harley is physical attractiveness. If you are not physically attractive to someone due to obesity, the chemistry so important in the early stages of a relationship may not be there. Likewise, if you have become overfat since the start of the relationship, you may not be able to provide that emotional need for your partner. By all means try to change our societal view of beauty, but the current reality is what it is,

Self-esteem: If you are obese, love yourself. It is a physical condition, not reflective of who or what you are as a human being. Nonetheless when people judge you continually it is hard to to keep your head up.

External perception: If you are obese, it is likely that many people will look at you differently. People do judge books by their covers. It's not fair. It's real. It crosses all cultures.

Underlying issues: If obesity is a reflection of an underlying issue such as metabolic syndrome (insulin resistance, high blood pressure, high triglycerides, low HDL, and central body obesity), it may be a signal of unhealthy lifestyle and eating habits that can lead to heart disease. Much obesity in the United States is reflective of these underlying issues. Do not use the articles cited at the beginning of this post as a reason to not take care of yourself. Obesity either carries risks or is symptomatic of other risks.

This blogger has an interesting perspective. Her viewpoint is that obesity is a fact and part of our culture. We should learn how to medically treat people with obesity rather than simply blaming their problems on the obesity.

Obesity is a charged word. Some people hear it and think bad things about someone. Others hear it and get angry because we as a society are not "fat-accepting." Whatever your weight is, you are beautiful. You are you. Accept yourself for what you are today. You may wish to make changes, but first, love yourself.


The following link is a tool that can assist you in measuring your body fat percentage. It's cheaper than a Tanita scale and can give you another perspective on your health.

Take Care of The Black Box - Exercise for Health, Not Weight Loss

I have written enough for now about how eating affects your physical well-being. Next up, exercise.

Many people believe that exercise is a great way to lose weight and keep trim. This fits in with our societal beliefs that obesity is caused by eating to much and not exercising enough, or as Taubes calls it, "gluttony and sloth." That is generally not true, and research backs it up. This recent study conducted by the University of Pittsburgh shows little difference between the exercise groups on a low fat diet ('Weight loss did not differ among the randomized groups at 6 months' (8%-10% of initial body weight) or 24 months' (5% of initial body weight) follow-up.") and the initial weight loss comes back on the same trajectory regardless of amount of exercise. Their conclusion was that 275 mins per week of vigorous exercise in addition to calorie reduction is "important in allowing overweight women to sustain a weight loss of more than 10%." They didn't mention that the women who actually ended up 10% lower weight were also restricting their Calories more than the others. This is a typical case of cognitive dissonance, seen in research all the time.

Here is a pretty good analysis of the study. She has access to the paper and data that I don't. Be careful though. She also says that long term weight loss doesn't happen at all, because of the "setpoint." She's wrong about that. Here's an analysis of another study that shows that physical activity correlates with higher weight. It doesn't address the composition of the weight however (fat vs. muscle).

This is a discussion of another study that shows that society has increased its level of activity, even while obesity rates have been increasing. It puts another nail in the coffin of sloth.

So why doesn't exercise work for fat or weight loss? There are a few ways to look at it. First, and most simply, burning significant calories through exercise takes lots of time and work. An hour of heavy aerobic work by a medium sized person might burn 600 Calories or so above your basal metabolic rate. One hamburger undoes all that.

The other more basic issue is that when you burn those calories through exercise, you are using the fuel in your body. Your cells still need fuel and to the extent you exceed the fat burning capacity of your system, you will feel hunger. Fundamentally, exercise does not blunt hunger like a proper diet can, so it becomes much less automatic and prone to failure. Some people ramp up the exercise and "willpower" their way into additional weight loss, but if you exceed the capacity of your body to burn its own fat, the weight loss will come from muscle instead of fat, and your metabolism will slow down because it senses starvation.

A Thought Experiment - Some Weight Loss Scenarios

You have a guy. He's in ok cardiovascular shape, carrying a little extra fat. Let's say he's are 6' tall, 200 lbs and 20% body fat. His daily energy need is 2,500 Calories. He decides to lose weight. What will be the outcome of the different approaches?

Note: In physics class you learned that a calorie is the amount of heat needed to change the temperature of 1 ml of water by 1 degree centigrade. In nutrition, a Calorie is actually a kilo-calorie (kcal). I have generally tried to follow the convention that capital-C Calorie is a kcal.

Scenarios
Diet-only Approach
Cut carbs, get plenty of protein, restrict calories to 1500 calories per day.

Exercise-only Approach
Eat normal, standard American diet (65% carbs, 20% protein, 15% fat), exercise 600 calories beyond BMR per day.

Intense Exercise and Diet Approach
Cut back on calories as in the diet-only approach. Do lots of aerobics and resistance training (600 calories per day) to enhance the calorie deficit.

Outcomes
Diet-Only Approach
The subject will have a caloric deficit of about 1,000 Calories per day. This will result in a weight loss equivalent of 7,000 Calories or 2 lbs of fat per week. He is carrying about 40 pounds of fat initially, so he will be able to burn a maximum of 1,240 Calories of fat from his body per day. Assuming his low-carbohydrate approach minimizes insulin response, the majority of the calories should be from fat. As he loses weight his ability to burn fat reduces, so he will have to run less of a deficit. Once his body adapts to fat burning, he will likely not feel terribly hungry most of the time.

Exercise-Only Approach
The subject will have a caloric deficit of about 600 Calories per day. This will result in a weight loss equivalent of 4,200 Calories or 1.2 lbs of fat per week. He is carrying about 40 pounds of fat initially, so he can support up to 1,240 Calories of fat from his body per day. One troubling aspect of this approach is that the realtively high carbohydrate content of his diet will likely induce an insulin response and thus inhibit fat-burning. Even though the net calorie restriction is less than the diet-only approach, the subject will feel hungry more and will have to "willpower" his way through to losing weight. With this type of approach, weight gain is highly likely if his routine is interrupted.

Exercise and Diet Approach
The subject will have a caloric deficit of about 1,600 Calories per day. This will result in a weight loss of 10,200 calories per week, or almost 3 lbs of fat. There is a potential pitfall here though. He will be exceeding his body's ability to use its own fat stores by about 360 Calories per day. His low-carb approach will allow for use of his fat as fuel, but once that reaches its limit, he will cannibalize muscle for fuel. This will cause hunger, and likely big drops in his metabolic rate. He will have a lack of energy and his physical capacity will decline.

What Does This Tell Us?
The bottom line is that fat-loss is limited by the body's ability to use internal fat as fuel. Fat loss can occur through either exercise or diet. Just don't push it too hard. Resistance exercise will help maintain muscle strength and also signal your body to send protein to the muscles that have been worked. If the combination of what you eat, plus what you burn from your fat stores is equal to or greater than your caloric needs your muscle loss (or catabolism) will be minimized.

On a low carbohydrate diet, your ability to replenish fuel for your muscles will likely be inhibited in the case of high-intensity or longer medium intensity exercise, so you may wish to increase carbs somewhat for those purposes. I think of it as "buying carbs" with high-intensity exercise. If you don't get sufficient carbs before high-intensity exercise you may bonk (run out of muscle fuel). Here's another interesting perspective on the bonk. With low intensity exercise (walking or light aerobics), you should be able to use fat for the majority of your energy needs.

This link will allow you to look at your own numbers. you will need to export the spreadsheet to your own computer.

But Lots of People Use Aerobics to Keep Trim

We all know people who eat whatever they want, then maintain a super-active lifestyle and so never put on any weight. So those people can argue that exercise is what keeps them thin. But the method contains the seeds of failure. Eventually, most people will get injured or sick. When that happen, people with poor diets and lots of activity will tend to put weight on rapidly. They are swimming upstream with their approach to weight loss and maintenance. You can make progress, but if they stop paddling for a second, they lose everything and then some.

Net calories matter, but it's only part of the story for weight loss. Spark of Reason blog has a great write-up on conservation of energy.

To lose or maintain weight, get your diet right first as spelled out in my previous posts here, here, and here. Do exercise to build and maintain muscle and fitness. If you are going to make one change in your life to affect your weight and fitness, fix your diet first.

Why Exercise Then?

Exercise carries many benefits not related to weight loss. Regardless of the weight issue, exercise has a number of benefits including: physical appearance, maintenance of muscle, confidence/self esteem, ability to be active, improved blood pressure, plus chemical advantages, such as increased High Density Lipoproteins (HDLs). I will cover that in future posts.

Addendum 8/15/08: Exercise, especially resistance exercise, might cause weight to increase (by increasing muscle mass). It's good weight though. Even though your BMI may go up, you will also be decreasing your percent body fat.

Healthful Eating

Part of what makes us tick emotionally is our physical state. I believe that our responses in any given moment are driven by the complicated balance of the chemistry of our bodies combined with how it interconnects through our neural network. So in a sense, we are big complicated computer programs that are constantly being recast by our experiences, learnings, and interactions.

From Pink Floyd Eclipse:

...All that you eat
And everyone you meet
All that you slight
And everyone you fight.
All that is now
All that is gone
All that's to come
and everything under the sun is in tune..."

It follows that if we want to change outcomes in our lives, we have to change either the inputs to our body, change our body, or both (because changing the inputs changes our bodies—reprograms it).

I have written about communication, the nature of love, vacation, and other issues dealing with emotions and relationships, but only recently have I delved into the physical side, specifically diet. These have proven to be my most popular writings since I started writing Emotions for Engineers about a year ago.

After a run-in with gout right before Thanksgiving in 2007, I decided I really needed to do something about my diet. I set out on my voyage of discovery. I chanced across Gary Taubes' "Good Calories, Bad Calories" and this lecture that he gave at Berkeley. It completely changed my views on eating and diet. Since Thanksgiving, I have lost 30 lbs of mostly fat, and for the first time in my life feel in control of my body.

Why we want so much to “be thin” troubles me. Most of us have two competing emotions—love and fear—that drive our decisions. If we want to lose weight because we want to look good for our spouses, that’s love. If we think that he or she will leave us for that ditzy young secretary if we don’t lose weight, that’s fear. Eating right because you don’t want to die is fear. Eating right because you want to be active and live long to see your grandkids is love. It can only be good if eating right and being at a healthy weight helps you feel better about yourself.

Fear is a harmful emotion that is driven by unknowns and doubts. As such, when we feel out of control concerning weight and fitness, as many do, the lack of control leads to fear, which can lead to depression, anxiety, co-dependence, and other bad things (not to mention the dark side). At the foundation of all we are, is our physical health. If you can gain some degree of control over that, the world will be better. You will have less fear in your life and allow room for love and growth.

My message is to look deep and be brutally honest with yourself. M. Scott Peck says that mental health is “Commitment to reality at any cost.” Find your motivations and if they are negative, try to recast them in a positive light.

Then take control...

Disclaimer: I have done a lot of independent study on this material and believe it to be true, safe, and effective, but I am a blogger, not a doctor. I am my own guinea pig and am not recommending anything that I have not done myself. Nonetheless, everyone is different. Your mileage may vary on this. If problems develop from any recommendations, seek professional help.

It's Not About Losing Weight--It's About Losing Fat

Weighing yourself may or may not be a good indicator of progress. Our bodies are made up of muscle, fat, water, and everything else. When most people talk about losing weight, they are hoping to lose fat. Water weight is easy. You can gain or lose five pounds in a day. But then you can't repeat it the next day. If you think you're overweight and want to shrink your muscles because you're too bulky, you are kidding yourself. Those aren't muscles—that’s the marbling making you big. Shrink the muscles and you'll be left with fat.

You want to convert your body and lifestyle into one that encourages usage of fat stores for fuel and discourages storage of fat.

So here are the two steps to a more healthy relationship with food.
1. Learn how to eat right.
2. Eat right.

Education
Most people blow it at step one. They read the government's food pyramid, follow weight watchers, or just cut back on portions. That might work for some people, but not most. So here are some facts.

1. You do not need carbohydrates to live and thrive.
2. Fat is an excellent fuel for low intensity activity (99.9% of the day for most of us).
3. Dietary protein and some fats (essential fatty acids or EFAs) are necessary for good health.
4. To lose weight you have to ingest fewer calories than you burn. (No surprise).

So there's the education part. Now here’s what to do about it.
Eat Mindfully
Now that you know what you need, you have a basis for acting on it.
First, make sure you get plenty of protein (shoot for 1 gram per lb of desired body weight). If you weigh 150, this means at least 150 grams (600 calories) of protein. Lean meat has 7 grams of protein per ounce. [Edit: I think that for active people probably 0.5 to 1 gram is ok. If you are actually trying to lose weight, i.e. restricting calories, cheat towards the high end on protein. Finally, if you are very obese (e.g. more than 50% above your target weight), you might want to think more in terms of desired weight rather than current weight.].
Second, limit carbohydrates, but get plenty of vegetables. Eat non-starchy vegetables like greens, cabbage, and peppers. Generally stay away from grain products including corn, bread, and pasta. If you must eat grains, eat whole grains in limited amounts. Definitely stay away from anything with added sugar, including High Fructose Corn Syrup (HFCS). Limit you total grams of carbohydrate to about 50 - 100 per day (200 to 400 calories). Sadly, ironically, artificial sweeteners, although they do not hurt you from a calorie standpoint may induce an insulin response, which can slow down your metabolism or make you hungrier. If you engage in high intensity activities, you can handle higher levels of carbohydrates.
Third, make sure you get some fats, especially omega 3s (fish oil). Don't worry too much about saturated vs. unsaturated, but stay away from hydrogenated oils (trans fats). The remainder of the calories needed should come from fat and more protein. There are lots of places on the web that will help you calculate your base metabolic rate.
Fourth, eat only when you are hungry. People eat for reasons besides sustenance. Sometimes there is an emotional attachment to eating in which food is used to medicate one’s psyche. This is a type of addiction. Other times people eat because it just tastes sooooo good or they simply don’t want to waste food. If you find yourself using food for emotional support or overeating at special events, try to find a way to stop that.
Fifth, keep an eye on the scale or your measurements or some other objective measure. If you are eating as above it will be hard to gain fat. Most weight loss would be from fat. Gains would more likely be muscle than fat. If you are gaining unexpectedly, cut back on carb and fat calories. You still need a calorie deficit to lose weight. I like to look at my weight on Thursday or Friday morning because it’s right before the weekend. Keep a log or spreadsheet if you wish.
Sixth, do resistance exercises that challenge your muscles. Exercise by itself is not an effective way to lose weight for most people. You should exercise anyway. It is good for you in many ways. Resistance exercise is good for everyone. It makes you stronger and sends a chemical message to your body to maintain muscle, even as you lose weight. Lift heavy enough to challenge yourself. If you can lift a weight more than 12 times, go to a heavier weight. The word “toning” has no meaning.

Following the above, most people should be able to maintain weight. The good news is that if you do want to lose weight, most of it would be from fat, not muscle. Your body will lose its reliance on sugar as a fuel and you will start to burn fat.

Seventh, limit weight loss to what your body can support. If you want to lose weight, the amount of fat you can lose is limited by the amount of fat you carry. You can burn approximately 31 calories per pound of bodyfat (bodyfat percentage times weight, e.g. 150 lbs at 30% bodyfat is 45 pounds of fat). Restricting calories more than that will lead to loss of non-fat weight. So in the example, total calories should be no less than your daily metabolic rate minus 1395 calories). The implication is that, at 3500 calories per pound of fat, this person can lose a maximum of about 2.8 pounds per week before crossing into non-fat weight loss. As you lose fat, this loss capacity diminishes.
Eighth and last, stick to the basics until you are on the right track. Once you do that, think about more details. There is an infinite amount of information on foods and supplements that you can pursue. Grass-fed vs corn-fed beef, farmed vs wild salmon, are thermogenics (like an ephedrine-caffeine stack) ok, sodium-potassium balance, meal frequencies, food combinations, etc. These things may make a difference in the long run, but you can be overwhelmed by the details, and at the beginning these issues are probably lost in the noise for most people.

Why Does This Work?

Nobody disputes the facts in the education section. But note how little resemblance there is to the food pyramid. When people follow the food pyramid recommendations, strange things happen to the body. The excess carbohydrates (grains especially) induce an insulin response, which drives nutrients into your fat and muscle cells. After a short time you feel hungry again. Even though you may have had a big meal, your cells are starving for energy. My grandmother used to talk about foods “sticking to your ribs.” Carbs do not do that; Protein does.

The body has many compensatory mechanisms, but excess carbs throw off the homeostatic mechanisms enough to cause fat gain. It doesn’t take much. Averaging 10 calories of fat deposition per day will add a pound in a year. Until my recent weight loss effort, I had been gaining about 3 lbs per year. That is only 30 calories per day.

This low carb approach has proponents and detractors. The problem I had with the other approaches is that I would lose muscle mass and energy. My experience with low carb has been incredible. I have lost 24 lbs since Jan 1, 2008, my weight lifts have stayed the same or improved, and I have seldom felt hungry. This has been close to an automatic program for me.

Some people say that losing weight is simply willpower. I don’t believe it. With low fat-high carb diets, people set up conditions that literally starve the cells in their bodies. In this starvation lies the seed of failure. Nobody can willingly starve himself or herself indefinitely. I don’t care how much willpower you have. You can’t hold your breath to death either. There’s too much science showing that these semi-starvation diets will not work. You need to give your cells enough fuel to keep them powered with the approach outlined above, the fuel not in your diet will come mainly from the fat in your body.

Eating a lower carbohydrate diet does have some potential side effects. At times, you may deplete your body’s stores of glycogen. This is especially true if you do high intensity exercise, which needs the sugar to fuel your muscles. At these times many people feel light-headed and foggy. I get the shakes a little and get a metallic taste in my mouth. It is called ketosis. Your body will adapt to this, but many people find it uncomfortable and stop the diet. The purpose of ketosis in this plan is to convert your body from needing sugar to fuel your low intensity needs, to using fat to fuel low intensity efforts. This is what the Atkins diet does in the induction phase. Some diets have a carbohydrate refeed day to refuel muscle glycogen and help reset the body’s metabolism.

The main takeaway for you is that most people can control their physical state. It is a question of positive motivation and the knowledge of how to do it. Removing health risks will allow you to focus on higher values. That can only be good. Happy trails.

In January 2010, I updated the recommendations in this post. target="_blank" It's quite similar, but there are some insights worth considering.


Links:
Emotions For Engineers
Gary Taubes' Berkeley Lecture
Good Calories, Bad Calories Book
Lyle McDonald
Protein Power Book, Protein Power Lifeplan Book, and Blog
Cross Fit – a combination of resistance and aerobic activity – if you dare
Ketogenic Diets – Comprehensive summary of advantages
Fat Loss Troubleshooting Guide from ProjectFit.org
Recent research comparing Low Carb, Mediterranean, and Low Fat diets



The following link is to a tool that can help you measure your progress on the road to better health.

Unified Feed Theory

When I looked at the previous post on taking care of the black box, I realized that there were way too many words and concepts. It lacked an engineering elegance, so I set out to express it in a way we engineers can understand--equations and graphs.

Before I even start, I want to clarify that the focus is on losing fat, not losing weight. Basically, we are all composed of fat, muscle, water, and everything else. We can think of "everything else" as a constant. Yes, bone density can change, organ size can change, but those are outside of the scope of this topic. Water weight can be lost and gained quickly by drinking water, eating, going to the bathroom, letting yourself get dehydrated, eating carbs. It can fluctuate by 5 or more pounds in a given day. We need a minimum level of hydration. We need to compensate for those changes. That leaves fat and muscle.

In general, more muscle = good, more fat = bad, all within limits of course. So when we talk about losing weight, the focus needs to be on fat. You don't want to lose muscle, and water weight is not relevant.

So the equation, expressed in Excelese is
DeltaBF = MIN ( MAX ( deltaE, -31.5 * lbs. body fat), k + f (Max(0, carbs in - 50)))

where:
deltaE is simply calories in - calories out (be careful, it's not quite that simple though).
lbs. body fat is weight * % body fat.
f (carbs in-50) is the slope of the upper limit on fat deposition related to the biochemical need of spent carbs in your system to store fat in your fat cells after allowing for 50 grams to fuel the brain.
k is some amount of body fat that can be deposited even on a zero carb diet through alternate biochemical pathways.

Lower Limit on Delta(FatDeposition)
A recent paper called "A limit on the energy transfer rate from the human fat store in hypophagia" helps us begin to understand how much fat we can take off in a given day. This estimates the amount of energy that can be removed from fat to fuel your body. The answer is (290+/-25) kJ/kgd.

Converting 290 *(239 calories/kJ)*(1Calorie/1000calories)*(1kg/2.2lb)= 31.5 Cal/lb fat +/-2.7

This effectively sets a limit on the maximum amount of fat you can burn each day with moderate activity and no steroids. It may be possible to lose more fat with activity because of the hormones excreted by that activity, but it seems like a reasonable way to think about it.

Note: As you lose body fat, the amount of fat you can lose in a day will decrease. Consider a 200 lb guy with 20% body fat. He is carrying 40 lbs of fat. So if he cuts his food intake by 1240 calories per day below basal metabolic rate, he can lose that much fat per day without eating into his muscle (lean body mass or LBM). Once he loses 10 lbs. of body fat, for example, he must limit his intake cut to 930 calories. Other metabolic changes are likely happening, for example, with cut in intake metabolism slows down, so that adjustment needs to be considered as well.

Upper Limit on Delta(FatDeposition)
The other day, I saw something on a blog. The author said something like, "If you're low carbin', calories aren't important. If you're low fattin', calories count."

For the low carb-ingestion cases, you can gain weight by eating lots of calories, but your body adapts to the high calories by upping your metabolism and giving you a sense of high energy. Even though ingesting low-carb, you will put on fat through some alternative metabolic pathways. It's just not as fast.

As you increase the amount of carbs that you eat. You open up a more efficient pathway for fat conversion. Your body uses the spent carbs to create triglyceride molecules. This is the primary storage form of fat. The slope of the line is a ratio of fat to carbs in a triglyceride molecule. I don't have that number.

The Ratchet Effect

You all know how a ratchet wrench works. It has a gear and a pawl, which prevent the socket from moving backwards. Its analog in electronics is a diode and in plumbing a check valve.

Simplified, biochemically you can store excess fat only if there are spent glucose molecules in your system. That is a well known, undisputed fact. So if you do not have spent glucose molecules, you can't store fat. Your body does not have a way to transport fats in your bloodstream into the fat cells. Your fat cells acts like a ratchet. It lets fat out if you are eating less than you burn, but if you eat more than you burn, your body has to find some other way to get rid of the fat (increasing your metabolism, fidgeting, pushing you out of your seat).

This is why if you're not eating any carbs, calories don't matter much. At worst, no fat leaves the fat cells. You can't get fatter.

The delta E Trap
What you lose is equal to what you eat minus what you burn. Burn more than you eat you lose weight; eat more than you burn you gain weight.

DeltaE is a common way of thinking about weight loss. It is a true relationship, but there is complexity in the relationship between the composition of what you eat and delta E. In fact, there is reason to believe that what you eat, more than simply being an independent variable is actually a driver of deltaE. I think the basic energy equation should be written as
E(out) = E(in) - deltaE. In fact, it is perhaps better to think of it as a giant feedback loop, because the calories you eat actually alter your metabolism as well over time.

E (in)
We as a society often see obese people and think that they have no willpower. They must be either pigs (gluttons) or lazy (sloths). But they are no different than any of us. When they feel hunger they eat, when they have energy they play. Let's think about this. People eat because a. they feel hungry or b. social pressures or pleasure. Hunger is not a character defect. We all know obese people who do not eat much, but stay obese anyway. What is the driver there? Something is altering the energy balance away from the balance that leaner people have.

In general, if you don't feel hungry, you should not eat. Your body's cells do not need anything in that moment. If is likely that sustenance will be stored as fat. The key is to eat right so you don't feel hungry before you need the sustenance.

Delta E
When you eat carbohydrates, especially simple carbs like sugar, white rice, or white flour, your blood sugar increases. This causes your body to put out insulin to regulate blood sugar. It does this by pushing that sugar into your cells, where it can be used for fuel. At the end the spent glucose then allows for deposition of fat into fat cells.

Now because the insulin has swept your blood clean of sugar, you begin to feel hungry. If you respond by eating carbs, the cycle starts again. The fundamental issue is that your body really wants to store carbs for later.

Repeat this, as we tend to with a Standard American Diet (SAD), and your muscles become resistant to the effects of insulin. You need more and more sugar to fuel yourself. Your body has trouble using its fat stores for fuel. This drives deltaE up and therefore E(Out) down. You gain weight.

You do not need carbohydrates to survive, your body will convert protein to sugar and use fat for fuel, but you want to ingest some carbohydrates to prevent the conversion of muscle into sugar (gluconeogenesis), as well as to prevent the feeling of foggy headedness that some people get when they eat low-carb. Lyle McDonald estimates a minimum of 50 - 100 g of carbs per day is good, more if you're doing resistance training.

Low Fat Enhances Storage of Fat

If you're on a low fat diet, it's different. In order to maintain your calories, you will likely be eating lots of carbs. This will then leave lots of spent carbs laying around in your bloodstream to hook up with those fatty acids. So if you are eating less than you're burning, you will lose weight. If you are eating more than you're burning, your body will push the excess into your fat cells.

Mindful Eating
At the end of the day, if you are paying attention to your weight, you can, in theory, lose weight by simple willpower. Those who have hormonal and enzyme issues, such as insulin resistance will have a more difficult time of it unless they eat right. For most of us though, we do not obsess over every calorie or gram that we eat. So we need a more automatic method. For me, limiting carbs has been a pretty reasonable automatic method. I have felt stronger than I have before when limiting calories and so far have lost almost 40 pounds.

But even with low carbs you have to eat mindfully. Eat only when you're hungry. Limit sweets. Pass up the cake at the company function. It's too easy to fall back into bad habits.

References:
Protein Power
BodyRecomposition

The following link is to a tool that can help you measure your progress on the road to better health.

Take Care of the Black Box - Eat Right

In previous posts, I referred to your body as a black box or a bag o' chemicals. The idea is that whatever you think, whatever you do, whatever actions you take or words you speak are initiated by chemical reactions in your body.

It is an easy step to go from there to ...therefore, a healthy body gives you a healthy mind.

I have recently had an intense focus on getting my body to a healthier state. There are two parts to that: diet and exercise. This post is about diet.

A recent book, Good Calories, Bad Calories by Gary Taubes has rocked my world.

Taubes has researched and documented the history of obesity and nutritional research since the mid 1800s. What he has revealed in the book is the likely cause of the slow motion train wreck of obesity and diabetes in the United States.

As you can see in the maps to the right, the incidence of obesity in the US has increased greatly since 1991. Diabetes, hypertension, and other chronic syndromes have followed similar trajectories.

Taubes has documented how and when the thinking about good diet changed from the idea that carbohydrates (especially highly processed carbohydrates) make you fat, to the current concept that carbohydrates are good for you.

On the line graph, obesity increases starting in the mid-1970s when George McGovern announced the publication of "Dietary Goals for the United States." This publication marked the beginning of the carbohydrate age. The American Heart Association began pushing a low fat, low cholesterol diet, and the USDA did the same.

In recent years, there has been an important paradigm, that weight change/obesity is driven simply by calories in minus calories out. Proponents of this paradigm cite the first law of thermodynamics. Their thinking is that energy in (what you eat) and energy out (what you use) are the independent variables with delta E being the simple difference between the two.

Taubes contends, with an enormous amount of reference material, that the composition of your diet actually drives the delta E, then your body does what it needs to do in order to either "force" you to eat more (by triggering hunger pangs for example) or by changing your base metabolism or activity levels. The laws of thermodynamics still apply. It's just that your body changes its requirements dynamically. In this model, obesity is not a failure of willpower or laziness (gluttony and sloth), but rather a biological imperative. It treats the body and metabolism as not just a calorie counter, but as a metabolically active organism. This perspective is more consistent with the results of multitudes of studies than the inert metabolically static model.

This bothers many people, because their belief is that obese people just don't care about themselves. Nothing could be further from the truth. We all know overweight people who eat tremendously low calorie diets and are unable to lose weight. Of course even when they go off the diet, they gain it right back and more.

Nutritionists have long known the following: Carbohydrate consumption drives insulin secretion. They also know that Insulin secretion drive fat deposition. These are known facts. As engineers you know that this is logically equivalent to "Carbohydrate consumption drives fat deposition."

So eating that tends to drive insulin secretion will tend to cause deposition of fat. This is known and has been known for a very long time.

In general, all else being equal, lower calorie intake will result in lower body weight. In an uncontrolled caloric environment (i.e. the real world), higher levels of carbohydrate ingestion will trigger an insulin response in your body, which will then leave your body craving more food. Repeat this many time and the cells of your body become insulin resistant, which will drive higher levels of insulin secretion. This leads eventually to metabolic syndrome, symptoms of which are diabetes, high blood pressure, central obesity, decreased HDL level, and elevated triglycerides. You can also get increased uric acid levels in your system, which can lead to gout.

The point is not strictly that carbohydrates are bad for you, but rather that the people who have been claiming that carbohydrates are good for you have done that without regard for basic scientific principles. And by the way, there is a preponderance of evidence that indicates that excessive carbohydrates are bad for you.

E4E's Advice

I had gained almost three pounds per year since I graduated from college in 1979. I have tried diets from time to time as well as exercise. What I found was that when I would try to do both, after a short time, it was really hard for me to exercise. I would become sluggish and feel unmotivated.

In late 2007, I decided to learn about this stuff and really make an effort to become a better animal by becoming more fit and losing body fat (not just losing weight). A bout with gout right before Thanksgiving really motivated me to learn about nutrition.

I started digging into website of people that I was familiar with. One of the first was Lyle McDonald's body recompostion website. Lyle is a science nerd who really likes to pore through research and extract the relevant and important information. This was a really good start. I learned a few things on this. First make sure you get enough protein. Try to consume at least 1 gram of protein per lb of body weight (this is a lot of protein). Second, you can cut up to 31 calories per pound of body fat out of your diet and lose minimal lean body mass.

From there I found several paths:

This Gary Taubes lecture at Berkeley contains the basics of what is in Good Calories, Bad Calories.

Paleo diet websites - These are all a little different in what they consider to be appropriate diet. I think they all favor lower carbohydrates (especially no grains).
The Paleo Diet has a lot of the science
Paleo Recipes recipes that follow a gluten-free philosophy
My Paleo Kitchen heavy on vegetables, fruits, and meats


Disclaimer: I am not a doctor or trained nutritionist. If you are contemplating changes in your diet or exercise, you should first check with a doctor. I also recommend that you learn about fat and carbohydrate metabolism, as I suspect that many doctors are not up to date on all those topics. Remember in all this, your mileage may vary.

Having said that, my basic conclusions from all of this are as follows:

1. Exercise is good for you, but it will not be the biggest driver of weight loss. It is important for your health and well-being to do both aerobic, resistance, and flexibility training.

2. Diet is an important source of good health and weight loss, so...
a. Eat plenty of protein. Somewhere around 1 gram of protein per pound of weight seems like a good number. (note: if you have problems with your kidneys, check with your doctor first).
b. Eating fat is OK. Stay away from trans fats generally.
c. If you are trying to lose weight, cut back on (primarily) carbohydrates to the tune of about 31 calories per pound of body fat. In my case, when I started out I was about 230 lbs at 20% bodyfat. I cut about 1200 calories per day. I could have cut more (230 * 20% * 31 = 1426), but this seems to be working. I'm losing so far about a pound per week, with very little decrease in my resistance training abilities. So far I'm down about 20 lbs. Use a Tanita scale or get a fat caliper measurement to determine your body fat.
d. Do not add sugar to food, stay away from sweets in general, and do not drink sweetened soft drinks. Even artificial sweeteners can elicit an insulin response.
e. When you do eat carbohydrates, generally try to stick to vegetables and fruit. Nuts are OK too (not sugared ones though).

So, take care of your body, and keep yourself in a place where you want to be physically. If you do that you will have a better chance of being emotionally healthy as well.

ABC or ABC

Many of you are probably familiar with the ABC framework for analyzing behaviors. ABC stands for Antecedent, Behavior, Consequences.

The basic idea is that Behaviors are a feedback system, mainly between Behaviors and Consequences.

A possibly useful way of looking at our responses to our emotions is the other ABC framework laid out by Albert Ellis, which I found in the book, How to Be An Adult by David Richo. "A" stands for activation, "B" is Beliefs, and "C" is consequences. It has to do with the topic of "owning your feelings" and anger. From my perspective owning your feelings means to understand where those feelings come from and responding to them appropriately. Understanding where the feelings come from is the key.

If we take our communication diagram from a previous post, we can group this ABC quite nicely in that framework.

Consider a situation in which you are driving down the freeway minding your own business, when suddenly, someone zooms past you and cuts right in front of you (Activation). You're ticked off, angry that this guy would cut you off, so you make some naughty hand gesture (Consequence). You might say that you are mad because he cut you off. In the ABC framework, the anger is not caused by being cut off, but rather by your belief as to his motives. In your belief system, people who cut you off are jerks.

Would you see it differently if you knew that his daughter was bleeding to death in the front seat and he was rushing her to the hospiital? If that were the case, your feeling might be one of pity rather than anger and you would move out of the way willingly.

This is closely related to the Fundamental Attribution Error (a very common bias), in which we attribute bad motives to others when we do not know their motives. A nice definition from Wikipedia is that people have an unjustified tendency to assume that a person's actions depend on what "kind" of person that person is rather than on the social and environmental forces influencing the person. Overattribution is less likely, perhaps even inverted, when people explain their own behavior.

This is a variation on the standard communication flow. The difference being that the message is often sent by an action. So when you feel a strong emotion over what someone has done, try to examine your beliefs and preconceptions, then verify with feedback before you respond. People often have very different motives than we attribute to them.