How to Become Smarter (16 page)

As for my own weight and physical health, I am somewhat overweight according to the body mass index (BMI) [
337
]. My BMI fluctuates between 28 and 29 depending on the diet I am consuming. Women tell me that I look fine and I am happy with my appearance. Despite being overweight, I haven’t had health complaints in a long time and received a clean bill of health recently.
^K
My view is that if a person gains a little weight on healthy food such as boiled potatoes and whole grains, this is “healthy weight.” Epidemiological studies suggest that excess body weight correlates with a shorter lifespan and with some diseases
on average
. But these studies lump together all overweight people, regardless of how they gained weight. There are many healthy people who are overweight. Winston Churchill lived to be 90 despite being overweight. It is possible to put on a little weight on healthy foods, such as boiled potatoes and whole grains. There is no reason to believe that with this weight gain you will have the same undesirable effects on health as a person who puts on weight on junk food. A recent study shows that the current health of people who are overweight is not different from that of people with normal weight [
741
]. In contrast, obese people (BMI greater than 30) tend to have worse health [
741
].

There is also some research showing that animal fat can have beneficial effects on mental state or mental performance. Just to remind you, animal fat contains a high percentage of saturated fat and cholesterol, whereas plant-source oils contain little or no cholesterol and little saturated fat. A study out of Switzerland compared the effects of a single high-protein, high-fat, or high-carbohydrate meal on healthy volunteers [
117
]. The high-fat meal that consisted of equal parts of plant fat (palm and soybean oil) and animal fat (double cream) resulted in the best mental performance, during the 3 hours after the meal. The high-protein meal produced an intermediate result (it consisted of fried chicken and eggs), and the high-carbohydrate meal (glucose, maltodextrin, and rice starch) overall produced the worst mental performance three hours after the meal. The study examined the following mental abilities: simple reaction time, choice reaction time, average muscle activity and its variation, accuracy in short-term memory, accuracy in peripheral attention, central and peripheral efficiency. Another line of evidence in support of beneficial effects of animal fat comes from studies on laboratory animals. This research shows that high-cholesterol diets can improve spatial memory [
276
]. (Animal fat is the primary source of dietary cholesterol.)

A high-fat diet known as the “ketogenic diet” is an effective therapy for treatment-resistant epilepsy. This diet is based on saturated fat such as cream and butter. A variation of the ketogenic diet, the Atkins diet, which contains large amounts of animal fat, produces the fastest weight loss compared to other diets [
119
,
269
-
275
]. It can also improve indicators of cardiovascular health and some measurements of psychological well-being in obese people [
277
-
279
]. My personal view is that the Atkins diet would be less controversial and more acceptable to healthcare authorities if it excluded fried meat and fried fat. The latter contain high levels of carcinogens and cholesterol oxidation products. I tolerate the Atkins diet much better if:

• it consists of boiled and pasteurized foods,
  
• excludes artificial ingredients (salt, preservatives, salted cheese, salted, smoked, and cured meats),
  
• during the induction phase, it includes once- or twice-daily cold showers (Chapter Two).
  

The latter procedure can reduce possible side effects of this diet such as fatigue, low mood, and headache. Dietary fiber supplements are useful in the Atkins diet because they are effective against another side effect, constipation. (On the subject of hydrotherapy, both hot showers or baths and a hot environment reduce appetite. Adapted cold showers have no effect on appetite, although daily use in the winter
may
increase food intake, based on my experience. It is not known whether daily use of hot showers is effective as a weight-loss strategy. In my experience this approach can have side effects such as back pain, muscle pain, skin irritation, and increased fatigue.)

In the state of ketosis (dietary carbohydrates are severely limited), high-calorie diets, such as the Atkins, cause a weight
loss
. On the other hand, during a normal metabolic state (there is a sufficient amount of dietary carbohydrates), high-calorie diets containing increased amounts of fat tend to cause a weight
gain
. Thus, the relationship of dietary calories and body weight is not a simple one. To give another example, raw-fooders, most of whom subsist on a vegan diet, eat a lot of raw fruit, which is a high-calorie food [
920
]. Yet raw-fooders tend to be underweight [
919
], despite consuming plenty of calories. This observation further complicates the relationship of calories and weight. I developed my own weight-loss diet, the “starchless diet,” which is not a low-calorie diet. It is not a low-carb diet either. In 2012, I lost 31 pounds (14 kilograms) on that diet, and I believe that it works because it excludes “fattening calories.” The description of the starchless diet is found in
endnote C1
.

Genetics also plays an important role and one person can become obese while another underweight when consuming an almost identical diet [
947
]. Different people also respond differently to weight-loss diets: for example, many people lose weight quickly on the Atkins diet, whereas some people do not. The majority of people regain weight when they stop dieting and long-term compliance with weight-loss diets is low [
274
,
954
,
1001
]. Surgical interventions such as gastric bypass surgery and liposuction are an option for those who can afford them. Gastric bypass surgery is the most effective treatment for obesity, with significant long-term weight loss and maintenance in more than 86% of obese people [
946
,
951
]. Dieting is less effective in the long run (2-20% success rate, depending the source and definitions [
274
,
952
,
991
]). Exercise alone is the least effective weight-loss strategy for obese people [
949
,
950
]. Recent Consumer Reports (2011) analyzed a number of different diet plans and concluded that the Jenny Craig diet is the most effective program judging by long-term adherence and long-term weight loss. Yet the results of this diet plan are satisfactory for overweight, but not obese people: the dieters achieved an average weight loss of 7.4 kg (~16 lbs.) and maintained it for about 2 years [
953
,
954
]. Note that there is a significant minority of obese people who are in good health. Some academic researchers who study obesity admit that the healthy obese will be better off if they do not try to lose weight. This is because their chances of losing a significant amount of weight and keeping it off by means of diets and exercise are about 10%. Weight-loss strategies carry substantial costs from the standpoint of time, job productivity, and money (often futile costs). Some weight-loss methods carry health risks (for example, surgery and prolonged fasting).

Going back to the cognitive effects of fat, some studies show that low-fat diets correlate with increased feelings of hostility [
280
], suggesting that dietary fat may play an important role in mental health. Studies on laboratory animals show that high-fat diets have antidepressant and antianxiety effects [
261
,
281
]. In humans, one statistical study shows an inverse relationship between consumption of animal fat and psychological distress [
852
].

In summary, the possible relationship between saturated fat in the diet and cardiovascular diseases remains controversial and many studies show that this relationship is either weak or non-existent. On the other hand, evidence exists that animal fat can have beneficial effects on mental functions. I must qualify the beneficial effects of animal by my personal observation and some published evidence [
1006
,
1007
] that dairy fat (cream, butter, whole milk, and sour cream) tends to promote constipation. For this reason, I eat fatty meat and fish but prefer low-fat dairy. Based on the above evidence, we can make some practical recommendations for healthy people:

1. Excluding animal fat from your diet is unnecessary since there is no proof that animal fat causes health problems in humans. The amount of animal fat in the diet does not correlate with either body weight or blood cholesterol level. Epidemiological studies do not constitute rigorous proof that saturated fat causes cardiovascular diseases. Whereas fatty meat and fish are unlikely to cause problems, some experimental evidence [
   1006
   ,
   1007
   ] shows that dairy fat promotes constipation; thus you need to be careful with dairy fat.
   
2. You need to avoid fried, grilled or broiled animal fat because it contains high levels of cholesterol oxidation products, which participate in the pathogenesis of cardiovascular diseases. It is best to cook fat at moderate temperatures (for example, boiled meat). This fat contains the same low amount of cholesterol oxidation products as raw fat, and therefore it should not have adverse effects on health. Additionally, fried, grilled, and broiled meats contain detectable amounts of carcinogens, which are almost undetectable in boiled or steamed meat [
   146
   ,
   152
   ].
   
3. If you are still afraid of animal fat, you can continue consuming lean meat and low-fat milk. You can try using high-protein diets that are based on those low-fat products. If you notice, however, that you feel bad on high-protein
   low-fat
   diets (headache, depressed mood, abdominal pain, or diarrhea), you may consider fatty animal products. For instance, you can eat animal foods that contain a natural amount of fat: regular fish and regular meat (15-25% fat).
   
4. This book does not advocate one permanent diet that you should adhere to for the rest of your life. Even if you are unconvinced by the above evidence of safety of animal fat, you may still consider using high-protein high-fat diets on a temporary basis. You can go on these diets when performing difficult mental tasks. At all other times, you can follow either conventional dietary recommendations or low-fat diets.
   

• Saturated fat is found mostly in animal products such as meat, milk, and butter.
  
• Studies suggesting that fatty meat is bad for health are inconclusive and plenty of studies show the opposite.
  
• Dietary cholesterol has no effect on blood cholesterol and dietary fat does not cause excessive body fat (obesity).
  
• There is no convincing evidence that dairy fat (butter, sour cream, whole milk) causes weight gain and cardiovascular diseases. Nevertheless, clinical trials show that dairy fat promotes constipation.
  
• Thus, you can safely eat fatty meat and fatty fish (boiled or steamed) and low-fat dairy products.
  
• Animal fat cooked at high temperatures contains high levels of cholesterol oxidation products (oxysterols), which are bad for health. The amount of oxysterols does not increase when you cook meat by boiling.
  
• The relationship of body weight and dietary calories is not a simple one; genetics has a strong influence on body weight.
  
• The Atkins diet (a low-carb, high-calorie diet) is rich in fat and in saturated fat in particular. Yet this diet causes the fastest weight loss compared to other diets. It also improves markers of cardiovascular health, such as measures of blood cholesterol.
  
• This author invented his own high-calorie weight-loss diet, the “starchless diet,” which is not a low-carb diet.
  
• Overweight people who can stay with the Jenny Craig diet plan can lose moderate amounts of body fat and maintain the lowered weight for at least two years. This program may not be effective for obese people.
  
• In the long run, compliance with any diets is low. There is about a 10% chance that an obese person will lose weight and keep it off by means of dieting and exercise.
  
• Gastric bypass surgery is the most effective treatment for obesity.
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If one has to prove that dietary changes can improve mental abilities, then it will also be necessary to demonstrate that some other dietary changes can worsen mental abilities. In my view, a good example of a “dumb diet” is the diet that consists of whole-grain bread and water solution of sucrose. This diet embodies the opposite of what the natural intelligence theory suggests a person should do in order to improve mental abilities. The
bread-and-sugar diet
, in addition to impairing mental abilities, causes an abnormal mental state as described below. I tested this diet on myself for 4 days once and for 2 days on another occasion, and I also tested similar control diets for several days each. The bread-and-sugar diet includes the most typical food additive (refined sugar) as well as grains cooked at high temperatures (bread). Bread contains acrylamide, a substance toxic to nerve cells at high doses (see
Table 2
). Boiled grains contain undetectable levels of acrylamide, and the composition of Maillard reaction products may be different from that in bread.