Is Shou-Ching to blame for our rice habit?

Posted by on June 23, 2011 141 comments

I thought I’d interrupt the lipid series to talk about the place of rice in our diet. This is also an opportunity to explain to those who haven’t read the book the logic underlying our diet.

The occasion: Cliff at PaleoHacks questioned our endorsement of white rice:

White rice is touted to be basically pure starch by Paul Jaminet on the basis that Asian people eat it so it must be healthy right?

Not exactly. Cliff goes on to express concern about phytate toxicity and low nutrient density. Rose (in the comments) was concerned about beriberi (thiamin deficiency disease).

There were a lot of great replies, especially Melissa McEwen’s. (Melissa found some statistics on the fraction of phytate destroyed by cooking, and improved Wikipedia’s data on phytic acid content of foods.) I got a laugh out of John Naruwan’s answer (which he intended to be humorous):

My theory on Jaminet’s apparent love of white rice is his Chinese wife. My own wife is Chinese (well, Taiwanese). When I explain that maybe white rice is not so good for optimal health, I get the speech about Chinese people eating rice for thousands of years, blah blah blah. Bottom line: you try telling a Chinese person that rice is anything less than good for you and you happen to be that person’s husband, well, basically you’ll be sleeping on the sofa for a week.

In fact Shou-Ching is as interested in good health as I am. She often makes the point that in traditional Chinese cooking rice was eaten more as a palate cleanser than as a staple calorie source. We like white rice, but if evidence showed it to be unhealthy we’d be equally quick to stop eating it.

And, John – Shou-Ching is so nice, when she gets mad at me she goes out and sleeps on the sofa!

The Logic Behind Our Diet

Although we consider our diet to be a “Paleo” and “Pacific Islander” diet (by the way – read Jamie Scott’s report from Vanuatu if you haven’t already!), we did not construct the diet according to the syllogism, “People (from the Paleolithic, or East Asia, or any other place or time) ate this way, and were healthy, so we should eat that way too.”

Rather, our approach is more reductionist and centered around nutrients and toxins. Our diet aims to simultaneously achieve two ends:

  • Obtain enough of every nutrient to be fully nourished. It shouldn’t be possible to improve health by adding further nutrients.
  • Eat so as to minimize the diet’s toxicity, by eating very little of any one toxin. Since “the dose makes the poison,” tiny quantities of diverse food toxins can be tolerated, but no one toxin should be abundant in the diet.

A third principle is that meals should be tasty and delicious. We believe our innate taste preferences evolved to help us be healthy, and therefore pleasurable meals are healthful meals. (This was our sticking point with Stephan Guyenet’s interpretation of food reward: see Thoughts on Obesity Inspired by Stephan, June 2, 2011.) Apart from healthfulness, however, we consider tastiness of food to be a positive value in its own right. Luckily we believe the most healthful diet is also the tastiest!

The Place of Rice in Our Diet

Any food which is low in toxins can be included in our diet. Low toxicity is the key, because a missing nutrient can be obtained from other foods – or from a multivitamin or supplement. But there are usually no antidotes to a toxic food.

Rice is very low in toxicity. Most rice toxins reside in the bran, so milled white rice is already low in toxins. The great majority of white rice toxins are destroyed in cooking.

As a result, cooked white rice is almost toxin free. Cliff worried about phytic acid, but the amounts in cooked white rice are small – lower than almost all other seeds, nuts, grains, and legumes, and about one-twentieth the level found in such foods as sesame seeds, Brazilnuts, and pinto beans, as Wikipedia (and Melissa) have pointed out.

Phytic acid is also not all that dangerous. It is a mineral chelator, which leads to minerals being excreted rather than absorbed. The primary risk is that it will induce a mineral deficiency. Because phytic acid preferentially binds iron, which can be dangerous, some advocate its supplementation.

We don’t agree with that, but we don’t consider the small amount of phytic acid in rice to be dangerous, especially given that we recommend a mineral-rich diet and supplementation with both a multivitamin and specific key minerals.

Optimize Diet, Not Foods

Nutrient density of an individual food is not an overriding concern. Only the diet needs to be optimized – not individual foods. It’s OK to eat a food that is low in nutrient density if other nutrient-rich foods make up for it.

Our diet derives only about 20% of calories from carbs. Even for rice lovers, rice is unlikely to provide more than half that, or 10% of energy. If rice is half as nutrient dense as alternative “Paleo” starches, it diminishes nutrient intake by only 5%. That’s easy enough to make up by eating more vegetables, liver, and eggs – or by taking a multivitamin.

Many Paleo dieters speak of “cheat” foods, as if it was somehow immoral, or a violation of the diet, to eat them. There are no “cheat foods” on our diet.

For instance, we’ll often eat strawberries with whipped cream sweetened with rice syrup. This is low in nutrients, but also low in toxins. It would not do as the primary food of the day, but as a dessert or snack it is quite healthy.

Glucose is a Nutrient

This is a point many low-carb dieters seem to forget. Macronutrients are nutrients too.

The body needs glucose. Glycoproteins and polysaccharide molecules like glycosaminoglycans are important structural components of the body; certain cell types rely on glucose for energy; and the immune system relies on glucose for generation of reactive oxygen species to kill pathogens.

If no carbs are eaten, the body has to generate glucose from protein. Glucose production may be insufficient or suboptimal. That was the point of our Zero-Carb Dangers series.

Of course, in excess glucose could become a toxin. But the same can be said for protein and polyunsaturated fats. We don’t exclude meat or salmon from the diet because they can be over-eaten. One shouldn’t exclude rice either.

Conclusion

A healthy diet should contain a diversity of foods. This will reduce the diet’s toxicity, improve micronutrient ratios, and increase meal pleasurability.

Rice should not provide a large share of dietary calories – probably not more than 10% – but there is no reason to reject it merely because it is a grain. True, it comes from a bad family. But it’s the good child. Don’t hold its relatives against it.

Blood Lipids and Infectious Disease, Part I

Posted by on June 21, 2011 65 comments

If there will be a general theme to our second year of blogging, it will be chronic infections – how they interact with the body to promote disease, and how we can use diet-related techniques to successfully combat them.

Blood lipids, such as LDL and HDL cholesterol, provide a fascinating window into health. We’ve already discussed both LDL and HDL (Low Carb Paleo, and LDL is Soaring – Help!, March 2, 2011; Answer Day: What Causes High LDL on Low-Carb Paleo?, March 3, 2011; HDL and Immunity, April 12, 2011; HDL: Higher is Good, But is Highest Best?, April 14, 2011; How to Raise HDL, April 20, 2011), but there’s quite a bit more to be said.

The extraordinary Portuguese blogger Ricardo Carvalho, better known as O Primitivo, of Canibais e Reis did some great work a few years back assembling World Health Organization statistics into an Excel database. One of the fruits of this labor was that he was able to correlate disease rates against serum cholesterol levels for all the countries in the database. His post about that is here and he created a great graphical representation of the results which I’ve reproduced here (click to enlarge):

There’s a lot of interesting information in this graph.

On the upper right are some correlation coefficients between serum cholesterol and disease incidence. Most diseases are either uncorrelated with cholesterol, or negatively correlated, meaning that mortality goes up as cholesterol goes down.

Minimum mortality is found in countries with average cholesterol between 200 and 240 mg/dl. Mortality rises sharply as cholesterol levels fall below 200 mg/dl.

No ecological fallacy

When aggregating over populations, it’s possible to get misleading results – an outcome called the “ecological fallacy”. However, I think this relationship is pretty solid.

It’s been confirmed in individuals in clinical trials. For instance, in the Japan Lipid Intervention Trial, here was the table of mortality as a function of serum lipids:

You’ll note that the “relative risk” of dying was lowest for TC between 180 and 260, LDL-C between 80 and 160, and HDL-C between 60 and 70.

The minimum mortality region of O Primitivo’s national samples falls right in the middle of the JLIT minimum mortality region.

Infectious disease mortality depends strongly on cholesterol levels

By far the strongest dependence of mortality on cholesterol levels is found for infectious diseases. Infectious disease mortality is shown by the dashed green curve.

Infectious disease mortality approaches zero where TC averages between 215 and 245 mg/dl. It rises very sharply as TC falls. Over a wide range of TC, for every 10 mg/dl drop in average TC, mortality rises by 200 infectious deaths per year per 100,000 population.

Other diseases are partly infectious in origin

As regular readers know, I believe that many other “noncommunicable” diseases are actually caused in part by chronic infections. Cardiovascular disease is one – atherosclerotic lesions are universally found to be infected, macrophages usually need to be infected in order to become “foam cells” which contribute to atherosclerotic plaque formation, and the infectious burden in lesions drives the risk of fragmentation of plaque into the clots which cause heart attacks and strokes.

If cardiovascular disease is partly due to infections, and the protective effect of cholesterol against infections is present here, then we should expect cardiovascular disease mortality (shown in the red dashed line) to rise as TC falls.

It does. Mortality from cardiovascular disease starts rising as TC falls below 205 mg/dl and rises by about 200 infectious deaths per year per 100,000 population for every 25 mg/dl drop in average TC.

Causality probably runs in both directions

We can’t directly infer causality from these statistics. Consider two possible directions of causality:

  • Serum cholesterol – LDL and HDL – help defend against infections. As long as you have these infection-fighting lipids in your blood, infections can’t kill you.
  • Infections destroy LDL and HDL, and the more severe the infection, the lower blood cholesterol goes. By the time the infection is severe enough to kill you, TC is very low. So countries with high infectious burden have both low TC and high infectious mortality.

The first line of causality is certainly true. I’ve already discussed the important infection-fighting properties of HDL – in fact I’ve argued that infection fighting, not cholesterol transport, is the primary function of HDL (See HDL and Immunity, April 12, 2011). As I’ll discuss, LDL also has immune functions.

The second line of causality is also quite likely. Pathogens evolve ways to suppress immunity; that is what makes them effective pathogens. If LDL and HDL are crucial for immune defense, then pathogens will have found ways to destroy or damage them.

In this series I would like to explore these interactions between blood lipids and infections a little more deeply. They may lead us to ways we can tweak our diet to improve our defenses against disease — or help doctors recognize under what circumstances taking statins will raise, not lower, cardiovascular disease risk.

References

[1] Matsuzaki M et al. Large scale cohort study of the relationship between serum cholesterol concentration and coronary events with low-dose simvastatin therapy in Japanese patients with hypercholesterolemia. Circ J. 2002 Dec;66(12):1087-95. http://pmid.us/12499611.

Happy Father’s Day; and Pictures From Our Vacation

Posted by on June 19, 2011 14 comments

Happy Father’s Day! Our best wishes to all Dads.

I’ll be spending part of today on Cary Nosler’s radio show this afternoon from 3-4 eastern time (12-1 Pacific) and you can listen on the Internet by clicking the “Listen Live” button at the top of his page. The interview will also be archived online and I’ll post a link when that is available.

Since it’s a day of relaxation, we thought we’d share photos from our vacation.

The primary motivation for this trip was to help the oldest of our wards, Samantha, move to Savannah, Georgia. Along the way we spent a few hours at beaches in Rehoboth Beach, Delaware; Ocean City, Maryland; Chincoteague Island, Virginia; Virginia Beach, Virginia; Wilmington, North Carolina; Myrtle Beach, South Carolina; and Tybee Island, Savannah, Georgia. We also spent a few days touring Chincoteague Island, Virginia and Savannah.

Here is a sampling of pictures.

Most of the beach towns looked similar. Here is a view of Myrtle Beach:

Savannah has a beautiful cathedral:

At the mass we attended an Irish priest told stories from his childhood: of “Montana Fitz,” a rare Irishman who had returned from the US, who told the children that the skyscrapers of New York were so high they had to cut out floors to let the moon pass through; and of being banned from the cinema for 6 months after he kidnapped a goat and smuggled it into the theater, raising havoc mid-show.

Here is a picture of me on River Street in Savannah, our nephew Hong is on the right:

Here is the oak drive into Wormsloe, an estate established by one of the original settlers of Georgia – and Paul and Shou-Ching:

Wormsloe had some salamanders which were good at blending into the background:

A Georgia crab:

Here is Tybee Island, Georgia:

A self-photograph:

A stingray caught by a fisherman at Sea Gull Pier on the Chesapeake Bay Bridge.

He was thrown back:

A salt marsh on the eastern shore of Virginia:

Some ducks:

On Chincoteague Island, a seabird eating our nuts:

An egret caught a fish:

A turtle:

Chincoteague Island is full of egrets:

One of these birds is having a bad hair day:

This one caught an eel:

I’m not sure what these birds are:

It’s also full of blue crabs.

We generally stay in efficiency suites so we have the option of cooking, and it paid off here as we spent an hour and a half crabbing and had a nice crab dinner.

I’m not sure if crabbing is hunting or gathering, but it sure is easy. We caught thirty 5” or larger blue crabs in an hour and a half and could easily have caught a hundred.

We also caught a pair of mating horseshoe crabs:

They walked off together:

Of course, Chincoteague is known for its wild ponies. They’re not always so wild:

Here they are grazing on marsh grasses:

Finally, sunset:

One Year Anniversary; and Vacation

Posted by on June 7, 2011 41 comments

The one year anniversary of our blog will be on June 14. The year has flown by, but it’s been very enjoyable for us. We’re delighted at all the new Internet friends we’ve made.

We’ve developed a fair-sized audience — about 24,000 unique monthly visitors and 120,000 monthly page views — and we’re grateful for every one of you. We’re especially grateful to those who have made our comment section one of the most pleasant on the Web.

To celebrate, we’re going on vacation for the next week and a half. It will be a genuine vacation — which means we won’t read or reply to comments or emails until our return.

Blogging will resume when I (Paul) get caught up on work. I may take a blogging break to get the Kindle version out, and make some changes to the web site.

Also, soon after getting back I’ll be appearing on a few shows: Cary Nosler’s radio show on KSTE Talk 650 in Sacramento, California on Sunday June 19 from noon to 1 Pacific time (3-4 pm eastern time); and Ben Greenfield’s podcast show. Looking farther out, I’ll be speaking at the Weston A. Price Foundation’s Wise Traditions conference in Dallas November 11-13. It will be a great meeting; many thanks to Sally Fallon for the invitation to speak.

When blogging resumes, first up will be a bit more on LDL, and then I’ll begin “My Story.” I’ll take long breaks throughout to explore issues that came up at one time or another — cancer (which my mother died from at age 33), Candida, acne, rosacea, C. pneumoniae, memory loss and dementia, impaired mood, neuropathy, fatigue. As I get into how I resolved my issues, I’ll talk about how to use self-experimentation to help diagnose causes and find effective therapies for chronic disease.

As we progress on our cookbook, I’ll blog posts about the health benefits of various foods, and how to adjust the diet for various health conditions.

I expect to have one or two guest bloggers on the topic of fitness, and I hope to spend more time on the blog discussing reader experiences and seeing if together we can make progress in understanding and curing chronic disease.

We’re looking forward to our vacation but also to getting back to blogging. It should be a busy and fun year. Thank you so much for making this past year fruitful, and for helping us explore the puzzles of diet and health in the year to come!

Best,