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Showing posts with the label paleo diet

Dr. Jekyll dieted and became Mr. Hyde

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One of the most fascinating topics for an independent health researcher is the dichotomy between short- and long-term responses in successful dieters. In the short term, dieters that manage to lose a significant amount of fat mass, tend to feel quite well. Many report that their energy levels go through the roof. A significant loss of fat mass could be considered one of 30 lbs, or 13.6 kg. This is the threshold for weight loss used in the National Weight Control Registry. Ideally you want to lose body fat, not lean mass, both of which contribute to weight loss. So, in the short term, significant body fat loss feels pretty good for the dieters. In the long term, however, successful dieters tend to experience the symptoms of chronic stress. This should be no surprise because some of the same hormones that induce a sense of elation and high energy are the ones associated with chronic stress. These are generally referred to as “stress hormones”, of which the most prominent seem to be c...

No fat gain while eating well during the Holiday Season: Palatability isolines, the 14-percent advantage, and nature’s special spice

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Like most animals, our Paleolithic ancestors had to regularly undergo short periods of low calorie intake. If they were successful at procuring food, those ancestors alternated between periods of mild famine and feast. As a result, nature allowed them to survive and leave offspring. The periods of feast likely involved higher-than-average consumption of animal foods, with the opposite probably being true in periods of mild famine. Almost anyone who adopted a low carbohydrate diet for a while will tell you that they find foods previously perceived as bland, such as carrots or walnuts, to taste very sweet – meaning, to taste very good. This is a special case of a more general phenomenon. If a nutrient is important for your body, and your body is deficient in it, those foods that contain the nutrient will taste very good. This rule of thumb applies primarily to foods that contributed to selection pressures in our evolutionary past. Mostly these were foods available in our Paleolithic ev...

Refined carbohydrate-rich foods, palatability, glycemic load, and the Paleo movement

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A great deal of discussion has been going on recently revolving around the so-called “carbohydrate hypothesis of obesity”. I will use the acronym CHO to refer to this hypothesis. This acronym is often used to refer to carbohydrates in nutrition research; I hope this will not cause confusion. The CHO could be summarized as this: a person consumes foods with “easily digestible” carbohydrates, those carbohydrates raise insulin levels abnormally, the abnormally high insulin levels drive too much fat into body fat cells and keep it there, this causes hunger as not enough fat is released from fat cells for use as energy, this hunger drives the consumption of more foods with “easily digestible” carbohydrates, and so on. It is posited as a feedback-loop process that causes serious problems over a period of years. The term “easily digestible” is within quotes for emphasis. If it is taken to mean “refined”, which is still a bit vague, there is a good amount of epidemiological evidence in support...

The low modern potassium-to-sodium ratio: Big problem or much ado about nothing?

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It has been argued that the diets of our Paleolithic ancestors had on average a much higher potassium-to-sodium ratio than modern diets (see, e.g., Cordain, 2002). This much lower modern ratio is believed by some to be the cause of a number of health problems, including: high blood pressure, stroke, heart disease, memory decline, osteoporosis, asthma, ulcers, stomach cancer, kidney stones, and cataracts. But, is this really the case? The potassium-to-sodium ratio in ancient and modern times According to some estimates, our Paleolithic ancestors’ daily consumption was on average about 11,000 mg of potassium and about 700 mg of sodium (salt). That yields a potassium-to-sodium ratio of about 16. Today’s ratio in industrialized countries is estimated to be around 0.6. Just for the sake of illustration, let us compare a healthy Paleolithic diet food, walnuts, with a modern industrialized food that many believe to be quite healthy, whole-wheat bread. The table below (click on it to enlarge) ...

The evolution of costly traits: A challenge to a strict paleo diet orientation

The fundamental principle of the paleo diet movement is that we should model our diet on the diet of our ancestors. In other words, for optimal health, our diet should be as close to the diet of our ancestors as possible. Following this principle generally makes sense, but there are a number of problems with trying to follow it too strictly. Some of those problems will have to wait for other posts. Examples are: our limited knowledge about what our ancestors really ate (some say: lean meat; others say: fatty meat); the fact that evolution can happen fast under certain circumstances (a few thousand years, not millions of years, thus recent and divergent adaptations are a possibility); the fact that among our ancestors some, like Homo erectus , were big meat eaters, but others, like Australopithecus afarensis , were vegetarians … Just to name a few problems. The focus of this post is on traits that evolved in spite of being survival handicaps. These counterintuitive traits are often call...