23 January 2010

Eat Food, Light on Carbs, Mindfully - E4E Nutrition Recommendations Revisited

In 2008, I published a series of nutrition posts.

The final entry was a set of dietary recommendations.

Since then diet and health has continued as a full blown obsession a special interest, I have read and studied a lot and and done a little self-experimentation. I have evolved my thinking to believe that something resembling caveman or paleo diets is the most healthful way to eat. Eat natural foods (don't shy away from meat), stay away from processed sugars, grains, and seed oils (which are relatively new in the human diet).

As I look back, I realize that I have a few modifications on the original post.

First, the original post recommended 1 gram of protein per pound of bodyweight. Although that amount won't hurt anyone, it is probably more than many people need. If you are a. engaged in intense physical activity or b. trying to seriously lose weight, that amount is probably ok. If you are not a serious athete and not trying to lose weight, most people can knock that back a bit. The US RDA is 0.8 g/kg of body weight (.36 g/ lb). I think that, as a minimum, most people should be in the 0.5 - 0.75 range. Protein has a lot of benefits including being the best food type for promoting satiety. (Aug 20, 2010 Edit: Some of my recent reading indicates that rather than bodyweight, lean body mass is a better benchmark. So a person who weighs 200 lbs and is 20% body fat should use 160 [200-(200*.2)] as the reference weight for protein consumption. This is still consistent with the above recommendations for most, but people with very high body fat may need to dial protein back a little).

Second, I recommended 50-100g of carbohydrates. I still think that's ok, even though many people can tolerate more than that without ill effects. Previously I said that healthy whole grains were ok. I'm retracting that now.

The carbohydrates you eat should come largely from vegetables. Not from sugar; not from grains.

Many people can tolerate grains (wheat, rice, etc.). But, I am hearing more and more about people who have coeliac (pronounced see-lee-ack) disease or an intolerance to gluten, a composite protein found in many grains. It also contains phytic acid, which, despite some potential therapeutic uses, also has myriad bad effects on teeth and mineral absorption. Bottom line is that grain provides nothing that is not easily found in other foods, and has lots of potential downsides. If you must eat grains, consider the advice given at Food Renegade (sprout, ferment, or soak). Stephan Guyenet at Whole Health Source has a number of informative articles about grains and phytic acid.

Compounds found in vegetables and many fruits are healthful (as opposed to the relatively empty calories of grains). Fruits may be over-sugary, so stick mainly with vegetables as the source of your carbohydrates. If you exercise intensely or are a competitive athlete, you may need to refill muscle glycogen. You can use starchy vegetables like potatoes or other tubers to do that, with little danger of ill-effects. If you must eat sugar, do so within about an hour of intense exercise (preferably after). Then your body will simply store it as muscle glycogen. That is pretty good advice for carbs in general as well.

Sugar, like grains, has little upside (besides the taste). Neither of these are required to sustain life, and there is lots of potential downside. One of the main issues with sugar is the fructose in it (see this video for an interesting perspective on fructose). This leaves vegetables as the best source of additional carbohydrates.

As a final note on sugar, fruit juice is not much different from a can of Coke. A 12 oz glass of orange juice has about the same sugar, and all you get extra is a little vitamin C and folate. That glass of sunshine is not what it's cracked up to be.

Third, I want to put a little more emphasis on the fats and oils in the diet. I said that you should stay away from trans fats, and that's still good. In general, oils made from grains (canola, corn) or soybeans requite a lot of processing to be edible. These unsaturated oils tend to oxidize easily and can lead to inflammation. I would lean more towards oils that require minimal processing. Do not be afraid of saturated fats like those found in dairy, coconut oil, and animal fats. A recent meta-analysis study shows that there is no evidence that saturated fats increase the risk of heart disease.

There is also the possibility that omega 6 to omega 3 ratio in our diet is causing problems across our population. Vegetable oils tend to be higher in omega 6. The best sources of omega 3 are fatty fish or fish oil and grass fed and finished beef. This is another reason to stay away from vegetable oils.

Fourth, I said to stick to the basics until you are on the right track. To clarify that a little bit, the basics include getting your macronutrient amounts about right (Protein: (20 - 40%), Carbohydrate: (10 - 20%),  Fat: (40 - 70%)). Minimize sugar and grain consumption. Cut back, in general, on vegetable oils. The more processing required to be edible, the more you should stay away from them. Use butter instead of margarine; lard instead of crisco (crystallized cottonseed oil). Do NOT stress over meal frequency. If you don't feel hungry, (more than just a grumbling belly), there's no pressing urgency to eat.

The basic concept is to establish a metabolism similar to what ancestral humans had pre-agriculture. This is not to say that you should do caveman food re-enactment, just that you want to eat foods that have the same overall effect on your metabolism.

One other thing, you don't have to be perfect about all this. Don't kick yourself if you blow one meal (or day). Sometimes, it is just a good thing to live a little. Don't ruin your health by eating something to which you are allergic, but if one night you have a scoop of ice cream, or you have some pasta with your daughter at her team's pasta feed, it's ok. Food events can be very personal bonding events, and it's ok. In fact, some of the diet folks, especially Lyle McDonald, incorporate carbohydrate refeeds to help normalize leptin, which then helps to suppress appetite. So once in a while, ease up a little, call it a carb refeed, forgive yourself, and move on.

Just doing the above will make a huge difference to many people. Going beyond that, some things to consider in my view of order of importance:

1. Take a vitamin D supplement, especially if you have darker skin, live in high latitudes, or get little unprotected sun exposure.
2. Consider pasture-fed meat and dairy products. The fat in those tends to be higher in omega-3 fatty acids and lower in omega-6. A corollary to this is to consider cutting out milk products altogether. Many people are sensitive to dairy and some do not think it is appropriate for humans. Here is Mark Sisson's take.
2a. If you do not implement 2, take a few fish oil capsules to supplement omega 3 fatty acids.
3. Consider consuming more organic produce in general. Less pesticides, chemicals, and other gunk.
4. Consider a vitamin K2 supplement or increasing foods with K2.
5. I do not encourage a vegetarian or vegan diet. It is obviously fine for some people, but many will have trouble meeting the protein requirements without lots of soy, and the oil content may be a problem. This is probably offset in many cases by overall reduced calories. Lierre Keith, a former vegetarian, recently wrote The Vegetarian Myth. I have not yet read it, but have seen a number of interesting and excellent reviews.

Some of my favorite sources:
Whole Health Source - refined grains, sugar, industrial seed oils are bad
Lyle McDonald - Nothing is good or bad per se. Food can help achieve specific goals.
Protein Power - More protein, less carbs. Drs. Michael and Mary Dan Eades. Also Sous Vide Supreme.
Summer Tomato - Foodie blog by a San Francisco Neuroscientist
The Paleo Diet, Loren Cordain - Paleo/caveman - No dairy, limited saturated fat ok
PaNu - Paleolithic nutrition. Establish an "Evolutionary Metabolic Milieu (EM2) not about food reenactment. Dairy ok.
Spark of Reason - Dave posts good info with sound logic. Give us more...
Free the Animal - Richard is a self-experimenter and paleo nutrition enthusiast. Lots of good info.
Zeroing In On Health - espouses zero carb lifestyle
Nephropal - Good science and understanding of hormones and biochemistry. Great information with a paleo bias. Here are their dietary recommendations.
Fat Head Blog and Movie - I highly recommend the movie. The blog has interesting and funny perspectives on many diet topics.
and of course, Good Calories, Bad Calories by Gary Taubes - I am not sure he gets everything right, but most of it is really good.