It's probably not a coincidence that H. pylori lowers stomach acidity. It's trying to feed itself. Lowering stomach acidity promotes poor digestion and extra food for hydrogen gas (H2)- producing bacteria further down the digestive tract. H. pylori thrives on the resulting increase in H2. There are countless examples in nature of parasites manipulating hosts to get what they want. A pretty simple example is Bordetella pertussis, the bacterium that causes whooping cough. It secretes factors that irritate the trachea, causing the victim to cough and thus facilitating its own spread through airborne droplets.
H2 is a high-energy molecule. In fact, it's being considered as an automobile fuel. It's also very small, allowing it to diffuse away from the digestive tract and throughout the tissues. Overproducing H2 in the digestive tract creates an all-you-can-eat buffet for whatever bacteria are present in the body that are capable of using it. As I mentioned in the last post, these bacteria include H. pylori, Salmonella and perhaps Clostridium. Nature abhors a vacuum. I'm sure there are organisms happy to siphon off some of this fuel. The interior of the body is relatively sterile, but there are plenty of bacteria hanging around the mucous membranes (nasal cavity, digestive tract, urogenital tracts) that could potentially exploit this energy source.
How do we thwart H. pylori and take back control of our stomachs? There are a few options. The first is to send in the big guns and take antibiotics. This is the standard treatment and it's usually effective, but I'm generally against antibiotics unless absolutely necessary due to their long-term effects on beneficial gut flora. Then there are other treatments like mastic gum, peppermint, gentian and probiotics, which may or may not be effective.
But the method I like best is starvation (of H. pylori). Obviously, the first step is to eliminate excess fructose, wheat, and anything else that causes digestive upset and gas. Several commenters on the last post mentioned that eating a "paleolithic"-type diet improved their digestion and reduced gas. That makes perfect sense to me, and it may actually be a very important effect of that type of diet. The same goes for low-carbohydrate diets. Two other weapons of intestinal flora starvation are chewing thoroughly and avoiding liquids during meals. The former allows you to absorb the maximum amount of calories from your food as rapidly as possible, leaving less for the bacteria. The latter makes digestion more effective by keeping stomach acid concentrated. A little bit of liquid such as a small glass of wine is probably fine.
If necessary, the next step may be to restore full stomach acidity, further cutting off the supply of H2 to H. pylori and breaking the cycle of reduced acidity, leading to increased H2, leading back to increased H. pylori growth. Sufficient stomach acid may also inhibit H. pylori directly, but there isn't much research on this. Restoring stomach acidity is pretty easy to do using betaine HCl supplements. Many people report improved digestion when they use betaine HCl. These basically release hydrochloric acid into the stomach, lowering pH. Most of them also contain pepsin, a protein-digesting enzyme secreted by the stomach. Buy them in capsule form rather than tablets so they dissolve rapidly.
Ideally, you should have your stomach pH checked to confirm you have insufficient stomach acidity before taking betaine HCl. If it's not lacking, there's no point in taking it (although trying it won't do you any harm beyond a little discomfort). But if you want to skip the expense, there are web pages that can teach you how to use subjective measures to determine if it's helpful for you. Some people feel that the stomach eventually "learns" to produce enough HCl again after a course of betaine HCl, after which they can stop taking it. This may reflect a suppression of H. pylori.
I think it's notable that healthy traditional cultures that ate plant foods didn't do it haphazardly. First of all, they typically ate the minimum amount of fiber necessary to get their calories. If they could remove fiber from their food, they did. For example, ogi is a widespread grain porridge eaten in Western Africa. To make it, you soak millet, corn or sorghum overnight. Then you pound it, mix it with water and strain it through a sieve. This removes the bran but allows most of the suspended starch through. The bran is fed to the animals, while the starch is fermented, cooked and eaten.
This is typical of healthy non-industrial cultures. They don't care about the glycemic index of starches, they care about maximizing digestibility and assimilation. In the process, they are minimizing food for their digestive flora. Fermenting grains before cooking may also reduce the amount of food left for gut bacteria. Starchy tubers and fruit (plantain, breadfruit) are also common features of healthy traditional cultures. They cook them thoroughly, sometimes mash them, and sometimes ferment them as well (e.g., poi).
Low-calorie vegetables are not staple foods in most of the world's healthiest non-industrial cultures, including hunter-gatherers. That's the main reason why I'm skeptical of the claim that eating immoderate quantities of vegetables is essential for health.
I do think it's worth mentioning that although they tried to minimize fiber, many (but not all) healthy non-industrial cultures nevertheless ate a lot of it and did just fine. It was inescapable for many of them. If you don't have the technology to remove rice bran, you have to eat it along with the starch. It may be just as well. Bran carries a disproportionate amount of vitamins and minerals. But it also comes along with a disproportionate share of toxins, which must be inactivated prior to eating by soaking, sprouting or fermentation. Healthy grain-based cultures knew this well, but we seem to have forgotten it in modern times.
Sugar, Hydrogen, Bacteria and Maldigestion
There are several ways to cause a nutrient deficiency. The first is to eat too little of a nutrient. Another way is to burn through your body's nutrient stores at an accelerated rate, for example, what omega-6 vegetable oils do to vitamin E, and what wheat bran does to vitamin D. A third way is to eat enough nutrients but fail to absorb them efficiently. A good way to reduce your absorption of nutrients is to lower your stomach's acidity. This will protect you from those pesky nutrients protein, vitamin B12, and iron (and probably others as well). The stomach is one tough organ. When it receives food, a healthy stomach lowers its pH to roughly 2.0 by secreting hydrochloric acid. That's more acidic than lemon juice and more than 10 times more acidic than vinegar. This begins to break food down, and will kill most bacteria and other pathogens. Stomach acidity is basically the body's way of "cooking" food before further digestion. At the same time, the stomach secretes pepsin, which is an acid-stable enzyme that digests protein.
Insufficient stomach acidity promotes bacterial overgrowth in the small intestine and allows undigested proteins into the intestine. The gastrin knockout mouse, which is incapable of producing stomach acid, suffers from bacterial overgrowth, inflammation, damage and precancerous polyps in its intestines. The same thing happens when you treat mice with a drug that inhibits stomach acidification.
There are a few different ways to reduce your stomach's acidity level. The most straightforward is to take an antacid, or any number of drugs that lower stomach acidity (as in the mouse study above). But can we do it naturally? Sure, all it takes is a little Helicobacter pylori infection! Luckily, most people already have one.
H. pylori is a bacterium that's the main proximal cause of stomach ulcers. Antibiotics are now the standard treatment for ulcers, and they're effective. Treating an asymptomatic H. pylori infection with antibiotics increases stomach acidity, suggesting that H. pylori is capable of suppressing the secretion of stomach acid. In another study, eradicating H. pylori with antibiotics improved nearly all patients suffering from hypochlorhydria (insufficient stomach acid).
Like any organism, H. pylori likes to stay well-fed. Its favorite food is hydrogen gas (H2), and the more it gets, the more it grows. It's not the only bacterium to like H2. Salmonella, of food poisoning fame, requires H2 to become pathogenic. Clostridium bacteria are also associated with elevated H2. H2 is produced by the fermentation of food by bacteria in the digestive tract. It's very small so it diffuses around the body, reaching the stomach lining where it's eagerly gobbled up by H. pylori. It may be equally good food for a number of other parasites around the body.
Now let's stop beating around the bush and get to the meat of this post. It's all summed up in a beautiful title: Fructose Intake at Current Levels in the United States May Cause Gastrointestinal Distress in Normal Adults. Dr. Richard W. McCallum et al. fed doses of isolated fructose to 15 normal adults. Can I say it any better than the abstract?
More than half of the 15 adults tested showed evidence of fructose malabsorption after 25 g fructose and greater than two thirds showed malabsorption after 50 g fructose... Fructose, in amounts commonly consumed, may result in mild gastrointestinal distress in normal people.Here's where it gets really interesting. One of the measures of malabsorption they used was H2 on the breath. Both the 25g and the 50g doses caused a large increase in H2, especially the 50g dose (5-fold increase). This is the same thing you see in people who are lactose intolerant. Bacterial fermentation is the only significant source of H2 in the human body. That means the fructose was hanging around in the small intestine for long enough to be decomposed by the local bacteria, who took advantage of it to proliferate.
Certain types of fiber also promote H2 production. Resistant starch, as well as certain non-caloric sweeteners, are readily fermented into H2 in some people. Cellulose, the predominant fiber in vegetables and grains, does not increase H2. The large difference in fiber content of rural vs. urban Mexican diets doesn't seem to correlate with H2 production by intestinal bacteria. Interestingly, both white and whole wheat bread increase H2 production.
Let's put those doses of fructose into perspective. One medium banana contains about 7 grams. A 16-ounce bottle of apple juice contains about 30 grams. A slice of cake contains about 12. One "child-size" 12 ounce cup of Coca-Cola from McDonald's contains 17 grams (as long as you don't get a refill!). One large 32 ounce Coca-Cola contains 47 grams. Your H. pylori will be VERY pleased if you drink one of those, especially if you use it to wash down the white flour bun on your hamburger.
I do think it's important to mention that the study described above used isolated fructose. It's not clear that other sources of fructose would behave the same. For example, the presence of glucose enhances fructose absorption. Fruit, table sugar and high-fructose corn syrup all contain glucose. It's also not clear what the effect would be of eating fructose with a meal rather than in isolation. None of this has been studied to my knowledge, so we're left extrapolating from studies that used pure fructose.
Now let's connect the dots. Excessive fructose, certain types of fiber, and wheat cause bacterial overgrowth and H2 production (if you believe the fructose-H2 connection). Elevated H2 causes overgrowth of H. pylori and possibly other pathogenic bacteria in the body. H. pylori lowers stomach acid, causing further overgrowth of bacteria in the small intestine. This causes inflammation and increases the risk for digestive cancers.
Decreased stomach acid also causes malabsorption of protein, B12, iron and perhaps other nutrients. It allows undigested protein to travel into the small intestine. This could potentially be very important. For example, many people are allergic to the casein in milk. It's one of the two most common alleriges, along with gluten. Both casein and gluten are proteins. A normally functioning stomach at the proper pH should completely digest casein. You can't be allergic to casein if there's none around. I don't know if the same applies to gluten.
Robust digestion may explain why many healthy non-industrial groups do very well eating dairy, sometimes to the exclusion of nearly everything else, yet many people in modern societies do better without dairy protein (butter is typically well tolerated). This phenomenon could also go a long way toward explaining the fact that allergies are becoming more and more common in industrial nations as we consume more sugar.
Thanks to Peter and Matt Stone for some of the ideas I incorporated into this post. Thanks to pbo31 for the CC photo.
Exercise and Bodyfat
I'm a firm believer that exercise is part of a healthy pattern of living. Hunter-gatherers had a word for exercise: "life". Getting outdoors and moving is one of the few things that differentiate modern humans from lab rats.
That being said, there are some common misconceptions about the activity patterns of hunter-gatherers and healthy non-industrial groups. They aren't (usually) couch potatoes, but they don't necessarily exercise a lot either. They range from very active to positively lazy, depending on the culture, the season and the gender concerned. Yet overweight is rare in all of them.
Consider the Kitavans. According to Dr. Staffan Lindeberg, the only overweight person on the whole island is someone who left for several years to live in a city. An average Kitavan man has a BMI of 20, which is very lean. Women have an average BMI of 18! A BMI of 25 is considered overweight and 30 is obese. The average Swede has a BMI of 25, the average American, 28. Kitavans have the activity level of a moderately active Swede, nothing more. They do the minimum amount of work required to grow their starchy tubers and fruit, and catch fish, all of which are abundant year-round. They are not restricted in calories.
Then there are the Tokelauans. Between 1968 and 1982, residents of the Pacific atolls of Tokelau gained roughly 11 pounds (5 kg) on average. This corresponded with a shift in diet from traditional Polynesian foods to a partial reliance on white flour, sugar and other processed foods. During this period, men exercised progressively less due to the introduction of the outboard motor, but the activity level of women stayed roughly the same. Both genders gained weight. Calorie intake didn't trend in any particular direction during the same time period.
Tokelauans who migrated to New Zealand saw a particularly large weight gain, gaining 22 pounds (10 kg) over the same time period. Their diet became even more Westernized than their relatives who remained on Tokelau. The authors of the Tokelau Island Migrant study felt that "most of the migrants expend greater energy in their work than is currently the case in Tokelau."
The "paradoxes" keep rolling in. In this recent study, investigators compared the energy expenditure of Nigerian and African-American women, using direct measurement (respiratory gas exchange and doubly labeled water) rather than questionnaires and observation. Here's what they found:
I think it's clear that the relationship between exercise and weight is not very tight. In my opinion, diet has a much larger influence on weight than exercise. Doing low-intensity "cardio" on a treadmill is almost totally ineffective for weight loss.
So can exercise help a person reach or maintain a healthy weight? Absolutely, but the type of exercise is critical. Exercise plugs into some of the same metabolic pathways as a healthy diet, normalizing hormone levels and increasing stress resitance. All you have to do is pop over to Chris's Conditioning Research to see a number of studies that compared chronic cardio (as Mark Sisson would say) to high-intensity, intermittent training (HIIT). HIIT is the winner every time by virtually every measure. Even though a person burns fewer calories sprinting on and off for five minutes than she does running for 30, she will still lose more fat and gain more muscle sprinting because of the metabolic shift that type of training produces.
In one study Chris posted, investigators compared the effect of two different exercise styles on fat loss and metabolic parameters. One group was assigned to low-intensity steady-state exercise, while the other was assigned to short 8-second sprints (called HIIE in this study). Here's what they found after 15 weeks:
That being said, there are some common misconceptions about the activity patterns of hunter-gatherers and healthy non-industrial groups. They aren't (usually) couch potatoes, but they don't necessarily exercise a lot either. They range from very active to positively lazy, depending on the culture, the season and the gender concerned. Yet overweight is rare in all of them.
Consider the Kitavans. According to Dr. Staffan Lindeberg, the only overweight person on the whole island is someone who left for several years to live in a city. An average Kitavan man has a BMI of 20, which is very lean. Women have an average BMI of 18! A BMI of 25 is considered overweight and 30 is obese. The average Swede has a BMI of 25, the average American, 28. Kitavans have the activity level of a moderately active Swede, nothing more. They do the minimum amount of work required to grow their starchy tubers and fruit, and catch fish, all of which are abundant year-round. They are not restricted in calories.
Then there are the Tokelauans. Between 1968 and 1982, residents of the Pacific atolls of Tokelau gained roughly 11 pounds (5 kg) on average. This corresponded with a shift in diet from traditional Polynesian foods to a partial reliance on white flour, sugar and other processed foods. During this period, men exercised progressively less due to the introduction of the outboard motor, but the activity level of women stayed roughly the same. Both genders gained weight. Calorie intake didn't trend in any particular direction during the same time period.
Tokelauans who migrated to New Zealand saw a particularly large weight gain, gaining 22 pounds (10 kg) over the same time period. Their diet became even more Westernized than their relatives who remained on Tokelau. The authors of the Tokelau Island Migrant study felt that "most of the migrants expend greater energy in their work than is currently the case in Tokelau."
The "paradoxes" keep rolling in. In this recent study, investigators compared the energy expenditure of Nigerian and African-American women, using direct measurement (respiratory gas exchange and doubly labeled water) rather than questionnaires and observation. Here's what they found:
Mean body mass index (in kg/m(2)) was 23 among the Nigerians and 31 among the African Americans; the prevalences of obesity were 7% and 50%, respectively. After adjustment for body size, no differences in mean activity energy expenditure or physical activity level were observed between the 2 cohorts.Are you bored yet? Here's another one, just in case your eyes are still open. I'll quote from Stefansson's Cancer, Disease of Civilization, referring to traditional point Barrow Inuit women in wintertime. The section in quotes comes from the anthropologist Dr. John Murdoch:
"They are large eaters, some of them, especially the women, eating all the time..." ...during the winter the Barrow women stirred around very little, did little heavy work, and yet "inclined more to be sparse than corpulent"One last example. Americans have gained weight continually over the last 40 years, despite increasing leisure-time exercise and an increased energy expenditure. Our calorie intake has increased over the same time period, and the quality of our diet has deteriorated.
I think it's clear that the relationship between exercise and weight is not very tight. In my opinion, diet has a much larger influence on weight than exercise. Doing low-intensity "cardio" on a treadmill is almost totally ineffective for weight loss.
So can exercise help a person reach or maintain a healthy weight? Absolutely, but the type of exercise is critical. Exercise plugs into some of the same metabolic pathways as a healthy diet, normalizing hormone levels and increasing stress resitance. All you have to do is pop over to Chris's Conditioning Research to see a number of studies that compared chronic cardio (as Mark Sisson would say) to high-intensity, intermittent training (HIIT). HIIT is the winner every time by virtually every measure. Even though a person burns fewer calories sprinting on and off for five minutes than she does running for 30, she will still lose more fat and gain more muscle sprinting because of the metabolic shift that type of training produces.
In one study Chris posted, investigators compared the effect of two different exercise styles on fat loss and metabolic parameters. One group was assigned to low-intensity steady-state exercise, while the other was assigned to short 8-second sprints (called HIIE in this study). Here's what they found after 15 weeks:
Both exercise groups demonstrated a significant improvement (P less than 0.05) in cardiovascular fitness. However, only the HIIE group had a significant reduction in total body mass (TBM), fat mass (FM), trunk fat and fasting plasma insulin levels.I think exercise is part of the fat loss / maintenance toolkit, along with intermittent fasting. But nothing beats a good diet.
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