How to Become Smarter (31 page)

On the surface, it may seem that emotional sensitivity is subject to free will,
^Q
i.e. you can become sensitive or insensitive at will whenever you want to. In my view, this notion is incorrect, and emotional sensitivity is difficult to control by a mental effort alone. Although you can change your behavior if you decide to pay more attention to others’ emotions, your intrinsic interest or indifference to the emotions of other people will remain unchanged. For example, a law enforcement officer may find it difficult to subdue and arrest a suspect if the arresting officer is too sensitive to the emotions of the suspect. As you can see from this example, low emotional sensitivity can be useful in some situations and is not a bad thing. Low emotional sensitivity is not the same as rudeness or offensive behavior.

The following techniques, which can increase or decrease emotional sensitivity, most likely change the “interest/indifference” component of emotional sensitivity. These methods are unlikely to increase accuracy of perception and understanding of emotion. At present, the biological mechanism underlying these methods is unknown.

In my experience, the most effective approach to increase emotional sensitivity is the fruit-and-vegetable diet (
fifth section
of Chapter Three and
Appendix II
). This diet contains negligible amounts of fat and protein. If other people tell you that you are rude and insensitive, you can try switching to the fruit-and-vegetable diet for several days. You will notice that you have become keenly aware of other people’s emotions. You may catch yourself trying to avoid causing even the slightest inconvenience to another person. Politeness should increase and you will be trying to avoid doing things that others may interpret as impolite. The awareness of other people’s emotions may reach the point of being uncomfortable. This is why emotional sensitivity is not subject to free will. While on this diet, it will be all but impossible for you to ignore other people’s emotions. You will be unable to change this state of affairs by a mental effort alone. On the other hand, you will be able to reduce your emotional sensitivity if you discontinue the fruit-and-vegetable diet. Also keep in mind that this diet will reduce your capacity for work and you shouldn’t stay on this diet longer than 3 to 4 days.

Another diet that can increase emotional sensitivity is the antidepressant diet, which we discussed in
Chapter One
. It consists of low-fat milk, wheat extract (
Appendix I
), fruits, vegetables, and unprocessed unsalted cheese. This diet contains significant amounts of protein and fat, but the protein is not of the highest quality. In my experience, this diet can make you more aware of other people’s emotions and more interested in the potential effects that your actions will have on others’ feelings. This diet is not as effective at increasing emotional sensitivity as the fruit-and-vegetable diet. On the positive side, it will not reduce your work capacity (with some exceptions for certain occupations). The antidepressant diet will increase emotional sensitivity to an above average level when the level is low or normal. This elevated level is within the normal range and will not become uncomfortable. If emotional sensitivity is excessive, for example, after an extended period of the fruit-and-vegetable diet, then switching to the antidepressant diet will lower emotional sensitivity to a more normal level.

The approach that can
reduce
emotional sensitivity is the modified high-protein diet (
Chapter Three
). It contains large amounts of highest-quality protein and is effective at improving attention control. This diet reduces emotional sensitivity, in that you may become less aware and less interested in emotions of others. Your ability to recognize and understand emotions of others will not change, but rather, you will be paying less attention to them.

This approach will not make you rude or antisocial—it will do the opposite. If you believe that you are rude and can’t help it or if you have difficulty getting along with other people, you can try this diet and it should reduce those problems. The reduced emotional sensitivity will manifest itself as the ability to ignore other people’s emotions and what others think about you. It can also manifest itself as increased bluntness and a tendency to poke fun at other people. This approach also makes it easier to observe or witness gross, disturbing or tragic events, which would traumatize sensitive people. For this reason, the modified high-protein diet may be beneficial in occupations that require low emotional sensitivity, such as surgery, law enforcement, and the military.

Some readers may be wondering what the cause of rudeness is if rudeness is unrelated to emotional sensitivity, according to my claims. Many vegetarians that I know believe that consumption of meat makes people rude and aggressive. One can refute this notion by testing an all-meat diet [
251
]. If meat does not make people rude (according to my claims above), then what does? My view is that the combination of bread with junk food and other “problem foods” listed in the natural food pyramid (
Table 3
) can contribute to rudeness. I do not have rigorous proof, but if I switch to this kind of dietary regimen, I become rude and heavy-handed in my relations with some people. I can’t help being rude under these conditions. The problem goes away if I exclude bread and junk food from the diet or reduce consumption of these foods significantly. Boiled grains do not cause this problem. These observations lead me to believe that rudeness involves a subtle cognitive impairment, which a person can reverse by a proper diet.

In conclusion, a question may arise: does emotional
insensitivity
(as defined above) correlate with thick skin, or a low propensity to take offense? In my experience, the correlation exists at the extremes (the fruit-and-vegetable diet and the modified high-protein diet). High emotional sensitivity correlates with thin skin, whereas low emotional sensitivity correlates with thick skin. This correlation does not apply to the antidepressant diet, which produces intermediate effects on emotional sensitivity. This diet makes the skin “somewhat thicker,” but at the same time, improves sensitivity to other people’s emotions.

• This chapter defines “emotional sensitivity” as the ability to pay attention to the emotions of other people and willingness to foresee other people’s emotional responses to one’s actions.
  
• The fruit-and-vegetable diet increases emotional sensitivity to uncomfortable levels.
  
• The antidepressant diet increases emotional sensitivity within the normal range.
  
• The modified high-protein diet reduces emotional sensitivity, which may be useful in some high-stress occupations.
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Warning:
The diet described in this section should not be used by patients diagnosed with depression or by anyone who suspects that they may be having a depressive episode.

Most high-protein diets contain significant amounts of cooked meat. Research shows that, in humans, high-protein diets can lower mood [
110
,
111
] and cause fatigue [
111
,
113
] and emotional tension [
110
,
114
]. Some high-protein diets, when combined with a regimen of physical exercise, can worsen mood [
110
,
111
]. There are studies suggesting that vegetarians tend to have better subjective ratings of mood compared to people consuming a mixed diet [
115
,
116
,
827
]. Even a single high-protein meal consisting of cooked chicken and eggs can lower mood in healthy human subjects [
117
]. My personal experience is in agreement with these findings. Cooked red meat, such as cooked beef, has the most noticeable mood-lowering effect, especially when I eat large amounts daily for one to two weeks (0.5-1.0 kilograms or 1-2 pounds a day). The mood-lowering effect of cooked meat disappears in the context of a ketogenic diet, that is, in the context of a diet that contains negligible amounts of carbohydrates, such as the Atkins diet. As explained in
endnote D
, self-experimentation suggests that raw meat does not lower mood in the context of any diet and has the opposite effect. (
Warning
: Readers should not consume raw meat because it carries a risk of infectious disease, see
Table 1
; there are safer ways of improving mood, as you will see in the next section
.) A recent research article shows that a single raw high-protein meal does not lower mood [
942
]. The high-protein meal in this study was based on cheese (made from pasteurized milk) and salami (made from uncooked meat). The above observations suggest that cooking of meat changes its effects on mood.

One possible explanation is that the brain of
Homo sapiens
had evolved on a raw diet and does not work well on the cooked diet. The evolution of the human brain started about 15 million years ago, when the first hominids or great apes appeared. This evolution continued through the time point about 300,000 years ago, when humans adopted fire for cooking. Therefore, it is possible that the human brain did not have enough evolutionary time to adapt fully to cooked meat and cooked grains. To some extent most people may be adapted to consumption of these foods and may experience only mild negative effects. Yet some genetically susceptible people may develop clinical depression
^X
when they consume a diet that contains large amounts of cooked meat and cooked grains. As a side note, epidemiological studies have shown an association between an unhealthy diet and depressive symptoms [
822
,
824
,
829
,
838
,
861
,
862
,
877
,
885
,
902
,
903
,
939
,
948
,
988
]. Some reports have shown that a healthy diet correlates with better mental health in general [
882
,
892
,
893
,
989
]. A recent research article shows that when monkeys switch to the modern human diet, they become more susceptible to depression [
934
]. The authors of this report are hypothesizing that the negative effects of the modern human diet are due to dietary cholesterol and saturated fat. (Yet another example of bashing of animal fat!) On the other hand, it is possible that the negative effects in the monkeys are due to the switch from a somewhat unnatural diet (laboratory chow) to an unnatural diet. This unnatural diet contains cooked meat, cooked grains, fried fat, and so on. The natural diet of most species of primates in the wild is a raw vegan diet [
44
,
45
]. There are some exceptions, such as chimps, who consume raw meat [
39
-
41
].

It took me awhile to figure out a possible mechanism of the mood-lowering effect of cooked meat. It turns out that this may be due to the small amounts of mutagens that form during cooking of muscle meats. As we saw in Chapter One, cooking of meat can form two major types of mutagens: polycyclic aromatic hydrocarbons and heterocyclic aromatic amines. (Readers can skip the technical details by pressing the skip button or
this link
.) The former are formed in significant amounts when you cook meat on an open flame. Benzo[a]pyrene is a well-known polycyclic aromatic hydrocarbon. Benzo[a]pyrene has a depressant effect on the central nervous system of laboratory animals, i.e. it makes the animals slower and less active at high doses [
172
,
173
]. It is unclear if the small amounts of this compound present in cooked meat have the same effects on humans. Another mutagen from this group, called pyrene, also has depressant properties in experimental animals at high doses [
170
].

The other major class of mutagens, heterocyclic aromatic amines, forms in meat during any type of cooking. The amount of these chemicals in meat increases with the duration and temperature of cooking [
136
,
146
,
165
]. Two of these chemicals, called harman and norharman, have psychoactive properties in laboratory animals [
199
,
446
,
447
].

Unfortunately, these chemicals exhibit antidepressant, rather than depressant effects in laboratory animals, and these findings do not support my argument here. Nonetheless, this research shows that, in principle, heterocyclic amines can have psychoactive properties. It is possible that some of the other 15 (or more) heterocyclic amines that science identified in cooked meat [
152
] can have the opposite, mood-lowering effect. Psychoactive properties of the majority of heterocyclic amines are unknown.