Yearly Archives: 2011 - Page 38

Around the Web; and the Corpus Clock

Posted by on February 5, 2011 11 comments

Every week I collect many more interesting links than I can blog about, so I thought I’d include in Saturday posts links to interesting material on the Web.

Here are some things I found noteworthy this week:

(1) Chris Kresser has concluded that 2 food pyramids are better than one. His fat and carb pyramids could serve as a visual summary of our diet:

(2) US children who regularly buy school lunches are 29% more likely to become obese than those who bring lunch from home.

School lunch programs have to follow official US dietary guidelines, which favor the subsidized crops of wheat, corn, and soybeans. The USDA recently banned the potato from school lunches in an effort to get kids to eat more grains.

Since food toxins cause obesity, this outcome is just what we would have predicted.

(3) Giving nitrate to athletes causes their mitochondria to become more efficient.

Spinach is rich in nitrates. Popeye was right! Spinach does make you stronger.

(4) More China Study data:  Ned Kock shows that fat is the safest macronutrient, animal food is safer than plant food, but that rice and vegetables are OK.

(5) Perfect Health Diet, the book, is “Paleo for engineers”. Accurate?

(6) Engineers, our video of the week is for you. When I first saw this thing, I thought it was a device for giving nightmares to young children.

Good thing Dr. Deans didn’t choose this for her kids’ nightlight! The blue lights are bad for melatonin.

Hunter-Gatherer Macronutrient Ratios: More Data

Posted by on February 3, 2011 59 comments

At the very beginning of our book’s macronutrient discussion (p 8), we offer four reasons to believe in a macronutrient intake around 30% carb, 55% fat, 15% protein – a relatively low-carb diet by modern standards. (Note: these ratios were updated slightly in our 2012 edition.)

One of them is that hunter-gatherer populations ate approximately in these proportions. Our cite was a 2006 review paper by Loren Cordain [1] that was based on an earlier paper (by Cordain, Janette Brand-Miller, S. Boyd Eaton, and others) in the American Journal of Clinical Nutrition [2]. These papers estimated hunter-gatherer diets from data in JP Gray’s 1999 corrected version of the 1967 Ethnographic Atlas of GP Murdock. [3]

The Cordain et al paper in AJCN was accompanied by an editorial from Katherine Milton [4] and a series of letters. Milton argued [5] that the underlying data was unreliable. Chris Masterjohn summarized her point in his review of our book:

Katherine Milton has pointed out (here) that when “casual agriculturists” and hunters that hunt with modern guns are excluded, Cordain’s 229 “hunter-gatherers” are reduced to only 24. Although Milton often seems biased in favor of plant foods, I’m not sure how much “hunter-gatherers” hunting with modern guns can tell us about what humans were eating 40,000 years ago.

The Ethnographic Atlas was compiled from anthropological contacts early in the 20th century, long after first contact of these peoples with modern societies. The peoples involved had changed their lifestyles based on trade, acquiring guns and other tools as well as access to agricultural goods. Milton was concerned that these acquisitions may have distorted their diets. Milton was also concerned that the (largely male) anthropologists who collected the data may have neglected the activities of women, who gathered plant foods, in favor of men, who hunted.

Milton presented no data of her own. Clearly it would be desirable to have data acquired directly from hunter-gatherer tribes not using guns or agriculture, and from a source other than Cordain and Eaton, whose version of the Paleo diet looks suspiciously influenced by the lipid hypothesis.

Well, we’re in luck.

Miki Ben Dor of the Hebrew-language blog Paleostyle has written to tell me of an interesting 2000 paper [6] by anthropologists Hillard Kaplan, Kim Hill, Jane Lancaster, and Ana Magdalena Hurtado in the journal Evolutionary Anthropology. Hurtado and Hill later became collaborators on Cordain’s acne paper [7].

Miki discusses the paper in Hebrew here. (Miki, by the way, wrote a very nice review of our book here.) For the benefit of those who don’t read Hebrew, I thought I’d present the data.

The Data

The authors present data on diets from nine hunter-gatherer cultures. The essentials are in this table (click to enlarge):

Seeds and nuts are significant only for the !Kung, who ate mongongo nuts, which provide primarily fat calories.

Fruit was a large source of calories only for the Nukak, Gwi, and Hadza. The “fruit” the Nukak of Colombia eat is the palm fruit, which has a small amount of starch but whose calories consist overwhelmingly of fat calories from palm oil. Palm oil is a healthy oil that is 50% saturated fat, 40% monounsaturated fat. The “fruit” the Hadza ate was also fatty, averaging 1200 calories/pound compared to 200 calories/pound for sweet fruits; sources included Baobab fruit and Kongoro berry. The Gwi San consumed melons, a sweet fruit.

Save for the Nukak and Hadza, the sum of root, fruit, and “other plant” intake is a fair approximation to total carb plus fiber calories.  These added up to 242 calories/day for the Onge, 137 calories/day for the Anbarra, 469 calories/day for the Arnhem, 277 calories for the Ache, 386 for the Hiwi, 300 for the !Kung, and 1200 for the Gwi. In all cases except the Gwi, carb intake was less than 20% of calories.

For the Nukak, carb intake was probably also in this range. So seven of nine cultures ate 10% to 20% carbs; for the Gwi San a majority of calories were carbs, and for the Hadza perhaps 40% of calories were carbs.

Meanwhile, foods obtained by men – primarily meat – provided 70% to 85% of calories for the Onge, Anbarra, Arnhem, Ache and Hiwi; 60% for the Nukak, about 50% for the !Kung, and 65% for the Hadza. [Table 2]

Another interesting observation from this data is that fruits were generally a less important source of calories than roots. It is likely that starches have outweighed sugars as a source of calories for humans for at least the last 2 million years.

Conclusion

In the book we argued that most hunter-gatherer cultures, when they weren’t constrained by Malthusian population pressures and famines, probably ate close to a 20% carb, 65% fat, 15% protein macronutrient ratio.

This data is largely consistent with that. Indeed, most cultures seem to have eaten slightly less than 20% carbs.

This paper does not provide sufficient data to break down the protein vs fat composition of the diets. But since protein seems to be eaten to a specific target of around 15% of energy / 360 calories by nearly all observed cultures, we can guess that that’s how hunter-gatherers ate as well. The acquisition of fat calories from fatty fruits and nuts, like palm fruits, confirms that fat was sought after.

The preference for starchy roots and tubers over sugary fruits is also no surprise. Not only are roots and tubers more calorie rich than most fruits, they are also (given the problematic nature of fructose) probably the healthier choice!

We don’t idolize Paleolithic or modern hunter-gatherer diets, so I won’t say that this data by itself proves our diet is correct. But I think it does add to the evidence that ancestral humans ate a diet that closely resembles ours.

References

[1] Cordain, L. “Implications of Plio-Pleistocene Hominin Diets for Modern Humans,” pp 363-383 in Peter S. Ungar, ed., Evolution of the human diet: the known, the unknown, and the unknowable, New York: Oxford University Press, 2006. http://www.thepaleodiet.com/articles/2006_Oxford.pdf.

[2] Cordain L et al. Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets. Am J Clin Nutr. 2000 Mar;71(3):682-92. http://pmid.us/10702160.

[3] Gray JP. A corrected ethnographic atlas. World Cultures J 1999; 10:24–85. Murdock GP. Ethnographic atlas: a summary. Ethnology 1967; 6:109–236.

[4] Milton K. Hunter-gatherer diets—a different perspective. Am J Clin Nutr. 2000 Mar;71(3):665-7. http://pmid.us/10702155.

[5] Milton K. Reply to L. Cordain et al. Am J Clin Nutr 2000 Dec;72(6):1590-1592. http://www.ajcn.org/content/72/6/1590.full.

[6] Kaplan HS, Hill KR, Lancaster JB, Hurtado AM. A Theory of Human Life History Evolution: Diet, Intelligence, and Longevity. Evolutionary Anthropology 9:156-185, 2000. http://www.unm.edu/~hkaplan/KaplanHillLancasterHurtado_2000_LHEvolution.pdf.

[7] Cordain L et al. Acne vulgaris: a disease of Western civilization. Arch Dermatol. 2002 Dec;138(12):1584-90. http://pmid.us/12472346.

Perfect Health Diet: Weight Loss Version

Posted by on February 1, 2011 396 comments

We started 2011 with a discussion of Experiences, Good and Bad, On the Diet; which led us into the issue of weight loss, especially for peri-menopausal and older women.

This is an especially poignant issue for erp, who is 76 years old and would like to lose weight for her upcoming knee replacement surgery, but cannot walk.

This is the toughest possible scenario for weight loss:

  • Whether for genetic (X vs Y chromosome) or hormonal reasons, women are more prone to putting on weight than men. (Men are more prone to diabetes.)
  • Hormonal changes after menopause seem to make it tougher for women to lose weight.
  • A petite woman doesn’t need as many calories as a larger person … but her micronutrient needs, and thus her appetite, may still be high.
  • Aging brings more efficient energy utilization and reduced energy expenditure. Thus, the elderly have a smaller energy “sink” in which to dispose of excess fat. A teenager can eat like a horse and stay thin; not so an older person.
  • An injury that prevents walking makes it even harder to burn off fat. Walking is a tremendous aid to fat loss.

Designing a weight loss diet for someone like erp really forces a hard look at how to optimize a weight loss diet. Get it even a little bit wrong, and the diet either won’t work for weight loss, or will be malnourishing.

The Three Keys for Weight Loss

The three keys for an effective and healthy weight loss diet, as I see it, are:

  1. Elimination of food toxins. Food toxins are the primary cause of obesity and you can’t expect to cure a condition by causing it!
  2. Perfect nourishment. The diet should be as nourishing as possible. The dieter should be in the “plateau range” of every nutrient – vitamins, minerals, organic molecules, carbs, protein, and fats.
  3. Calorie restriction. You have to be in energy deficit to lose weight.

The main food toxins to avoid are fructose, polyunsaturated fat, and wheat (see Why We Get Fat: Food Toxins). In my advice to erp, I suggested replacing some of her fruit with “safe starches” like potatoes, and replacing her PUFA-containing nuts with low-PUFA macadamia nuts or other foods.

But the harder part is achieving a calorie restricted diet when so few calories are being expended, and yet avoiding malnutrition. How may that be done?

Eat Protein and Carbs; Reduce Fat

This may surprise many readers, since we’re fat-friendly, but there should be no reduction in carb or protein consumption on weight loss diets. Calorie restriction should come out of fat.

The Perfect Health Diet “plateau range” for carbs and protein is 600 to 1200 calories. Eating less than 600 combined carb+protein calories per day raises the specter of either protein deficiency (leading to hunger) or glucose deficiency (leading to zero-carb dangers).

So if a typical daily intake is 400 carb calories and 300 protein calories, there’s really not much room to cut protein or carbs.

Remember that the body doesn’t have a significant store of carbs; the body’s total glycogen supply amounts to about a day’s needs. Nor does it have a store of protein, apart from skeletal muscle; and you don’t want to lose your muscle.

But it does have a large store of fat – those adipose cells that you want to shrink.

So to conserve muscle and reduce fat tissue, you have to eat your normal allotment of protein and carbs while restricting fat intake. As long as there is no serious dysfunction of adipose cells, they will release fat as needed to meet the body’s fat needs. And that’s what you want – fat being moved out of adipose cells to be burned.

So your calorie-restricted weight loss diet will be just as nourishing as your regular diet. Only the source of the nourishing fats – adipose cells instead of food – will be different.

Eat Nourishing Fats

But not all fat can be removed from the diet. The reason is that not all nutrients found in fat-containing foods are stored in adipose cells.

You see, fats are stored in adipose cells as triglycerides. But we need to get other lipid molecules, not just fatty acids, from food. The really crucial molecules are the phospholipids, especially phosphatidylcholine.

Choline, inositol, and a few others are organic molecules are bonded to fats in cellular membranes. We need to obtain these from our foods in order to be well nourished.

Diets low in choline strongly promote obesity. Therefore, anyone seeking to lose weight should be sure to eat a choline-rich diet.

The easiest way to do that is to eat 3 eggs a day and a ¼ pound beef liver once a week.

Another type of lipid that may be missing from adipose cells are omega-3 fats. Balancing the omega-6 to omega-3 ratio is helpful against obesity, and most people are omega-3 deficient. So eating up to 1 pound of salmon or sardines per week may assist weight loss.

Beef and lamb – meats that are low in omega-6 fats – would be good choices for any additional meat.

Be Super-Nourished

The body’s appetite regulation mechanisms are highly attuned to your micronutrient needs. Micronutrient deficiencies will tend to induce a strong appetite for food, as your body tries to get you to obtain more nutrition. This could be a major reason why “empty calories” such as cotton candy are fattening.

Our book has some examples of “micronutritious foods”: variety meats, bone soups, seaweed, shellfish, eggs, and vegetables.

Nutritious, low-calorie foods like bone soups can be very helpful for weight loss. Soups can also be a good way for someone who doesn’t like vegetables to obtain them.

In addition, I would recommend that every person on a weight-loss diet take our full supplement regimen: a daily multivitamin, D, K2, C, magnesium, copper, chromium, iodine, and selenium. Also, I would suggest taking our optional B vitamins: thiamin, riboflavin, pantothenic acid, biotin, vitamin B6, vitamin B12, and choline (note the exclusion of niacin and folic acid).

Keeping Calories Down

What is the minimum calorie intake that meets all these nutrient considerations?  Eggs, salmon, and beef have more fat than protein, so if you’re aiming for 400 carb calories and 300 protein calories, you’ll probably eat at least 500 fat calories per day. So it would seem to be impossible to go below about 1200 calories per day while still being well nourished.

The place to cut calories, then, is the extra fats. Perfect Health Diet favorites like butter, coconut oil, and cream are, sadly, top candidates for reduction.

Of course, the more active you are, the more you can include those fats.

For less active people, the Weight Loss Version of the Perfect Health Diet becomes similar to a lot of popular diets. Many diets recommend a roughly even calorie distribution, with 30-40% of carbs, protein, and fats. This is what a calorie-restricted version of the Perfect Health Diet should look like too.

So, the perfect day in a weight loss diet: soup, potatoes or other safe starch, salmon, eggs, vegetables. Not too much fat in the sauces!

A good meal might look like this:


Mash the sweet potato with eggs instead of butter, and this would fit our weight loss recipe.

Conclusion

It’s a little humbling that I’ve started 2011 with 5 posts on the subject of healthy weight loss, but have only scratched the surface of this complex topic.

For instance: In the book we used the rubric “metabolic damage” to describe the biological dysfunction associated with obesity. But we never really chased the complex biology of exactly that damage consists of – and how it can best be healed.

Today, I’ve presented what I believe is the best strategy for healthy weight loss. But other techniques – such as ketogenic dieting, intermittent fasting, exercise, and more – can contribute to healing the metabolic damage of obesity. As 2011 goes on, I’ll return to this topic.

I am intensely interested in the experiences of anyone trying to lose weight using our diet, and I hope that together, we can understand the disease of obesity better, and figure out good ways to achieve both healthy weight loss and a permanent recovery from metabolic damage of all kinds. So please, if you are trying to lose weight, keep me posted on your experiences, whatever they may be!

Related Posts

From 2011:

From 2010:

About Green Tea

Posted by on January 30, 2011 77 comments

Erich asked what kind of tea we drink. Tea is a subject dear to our hearts, so we thought we’d discuss it today.

First, some background. Over at Planet Tea they have a useful flowchart describing how different kinds of tea are made:

The critical step is fermentation, which oxidizes the leaf and turns it black. Green tea is unfermented; oolong (wu long) is partially fermented; and black tea (in Asia, “red tea”) is highly fermented. Black tea has a longer shelf life than green tea.

Growing region matters. Mainland China is by far the world’s largest producer of tea, but China is extremely polluted and we would not trust Chinese tea. Japan and Taiwan both produce excellent green teas; we drink tea from both countries.

Taiwanese Tea

The Taiwanese teas with the highest reputation are “high mountain tea”; these are grown at high altitudes above the smog. We drink both green and oolong high mountain teas from Taiwan. Ours come in 300 g vacuum-packed packages:

The one on the left is green tea, the one on the right an oolong; both are “high mountain” teas. Each package weighs 300 g. We use about 4 g (20 leaves) of tea per day, and so a package lasts about 3 months. A single 300 g package of high quality tea may cost $100, so the total cost is about $1 per day; but multiple cups of tea may be obtained from each day’s tea.

The leaves are rolled and dried during processing, and shrivel to a very small size, then re-expand when placed in warm water. Here is what they look like:

Left — rolled and dried leaves, ready to make tea. Right — an opened bud, after being used.

The opened bud on the right gives you a good idea what the leaves look like on the tea tree. Workers pluck these small buds from the trees and place them in baskets; the finest buds are plucked early in the spring.

Aside: Some Equipment

For best results it’s important to use pure water. Tap water produces a discolored tea with a foul taste. We get good results filtering our water in a Britta filter. In fact, we judge that it’s time to change the filter when our tea changes taste. The Britta instructions recommend changing the filter every two months, but we find it needs to be changed every month if our tea is to retain its flavor.

If you make tea often, it’s helpful to have a hot water dispenser, like this one from Zojirushi, along with your Britta filter:

Tea is best when the leaves have steeped for about 5 minutes. Since you may take much longer to drink the tea, it’s important to steep the tea in a separate container from your drinking mug. Here’s what we use:

Left — An Asian “busy person’s” tea-pot. A container at top holds the tea leaves and enough water to make a single cup. When the leaves are done steeping, pressing the red button drains the water into the pot, after which it can be poured into a mug. Right — an airtight container we use to store our tea leaves.

Alternatively, Asian supermarkets sell teacups in 3 parts — a mug, a container to hold the tea leaves, and a lid to cover while the tea is steeping. They look like this:

The tea leaves go in the removable upper part; when it is removed the tea drains through the holes in the bottom into the mug. After drinking a cup, the upper container with the leaves can be put back in and more hot water added to steep another cup.

Making the Tea

To make the tea, place 15-20 rolled buds into the leaf container, and add hot (near boiling) water. Taiwanese green tea typically requires 3 to 5 minutes to steep, and the tea is actually yellow, not green.

Shou-Ching likes her tea prepared the classic way. Add hot water to new leaves, and drain it after 30 seconds as the leaves just begin to open; this is thought to clean any impurities. Then add new hot water, let it steep 3 to 5 minutes, and drink this second batch. This produces a delicate, light yellow tea. Paul lets his steep a bit longer to make a slightly darker tea and adds a lemon slice. Here is what they look like:

Japanese Green Tea

Japanese green tea is made with a different process; the tea leaves are usually crumbled, not rolled. Here is what they look like:

These crumbled tea fragments are placed directly in the teacup and produce a green-colored tea. Yes, the tea leaves can be swallowed. Here is a comparison of a cup of Japanese green tea (left) with a Taiwanese green tea (right):

Obtaining Fine Teas

We are regularly sent tea by relatives and friends in Asia, so we haven’t had to shop for tea in the US.

However, Google searches turn up a number of vendors. “Tea from Taiwan” has some good-looking teas. Reader Gary Wilson kindly wrote to recommend Upton Tea Imports. And here are some Amazon links, not all currently available:

At roughly $1 per day, fine tea is not inexpensive. However, many people spend as much or more on coffee. Paul makes 5 or 6 cups per day from a single 4 g set of leaves, so the cost averages to only $0.20 per cup.

If your only knowledge of tea is derived from the Lipton Tea Company, we very much recommend that you give fine green or oolong teas a try! You might find tea more pleasant and enjoyable than you imagined.