How to Become Smarter (19 page)

Based on these observations, this book proposes the natural nutrition theory of intelligence (abbreviated as “natural intelligence theory”). This theory suggests that a raw diet, which is free of any artificial chemicals, will improve mental clarity. One implication of the theory is that a similar but safe diet should also improve intelligence. This is because those diets are similar to the diet of primates in the wild or to the diet of evolutionary predecessors of humans (the ancestral diet). Free-living primates do not consume any food additives and do not cook their food. This was also the case for evolutionary predecessors of humans before the mastery of cooking with fire approximately 300,000 years ago. The modern diet of humans for the most part consists of cooked and processed food supplemented with numerous chemicals. The natural intelligence theory suggests that the modern human diet has negative effects on mental abilities. This is because humans did not have sufficient evolutionary time to adapt to this diet through natural selection.

There are several limitations to the natural intelligence theory. Humans may have adapted to cooked food, at least partially, during the last 300,000 years of evolution. It is impossible to determine what a “natural diet” for modern humans is. On the other hand, numerous synthetic chemicals (food additives) entered the human diet only a few centuries ago. Therefore, the additive-laden diet may still be “unnatural” for the majority of the population. Another limitation of the theory is that raw meat and fish can contain pathogens that cause serious infectious diseases. This is a drawback of the presumed ancestral diet of humans.

Nonetheless, it is possible to design balanced diets that are both safe and similar to the ancestral diet. One example is a diet that excludes all artificial ingredients and consists of fruits, vegetables, water extract of grains, pasteurized low-fat milk, and unprocessed unsalted cheese. For convenience, I call it the “antidepressant diet.” Practical testing suggests that this diet improves intelligence in much the same way as the ancestral diet consisting of raw fruits, vegetables, meat, and fish. Cooking fruits and vegetables at moderate temperatures (by boiling or steaming) does not make any appreciable difference, and neither does pasteurization of dairy products. Addition of meat and fish cooked at moderate temperatures and nuts to the antidepressant diet will not worsen mental abilities on one condition. The amount of cooked flesh should not exceed the amount of dairy by weight. It is also possible to improve mental clarity by restricting the amount of food you consume, without adhering to a strict diet.

The proposed dietary changes can have side effects, such as character changes, and strict diets may cause problems in social relations.
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CHAPTER 2: Sleep management

This chapter describes several nonpharmacological treatments that can help a student or a knowledge worker to manage their sleep pattern. Please note that you shouldn’t skip a night’s sleep to cram for an exam or meet a report deadline. Chapter Five discusses procrastination and ways to reduce it to avoid such situations. Occasionally, however, shift work or unexpected circumstances may force you to stay up all night. Thus, you may need some techniques for staying awake and then for restoring a normal sleep pattern. Besides, if somebody promised to help improve your mental abilities, their advice would be useless if you couldn’t control sleep and wakefulness. In this chapter, we will talk about sedative (sleep-promoting) treatments first, and then about approaches to improving wakefulness.

One simple treatment for promoting sleep is moderate heating of the body. One study on patients with dementia showed that immersion in hot water at 40°C (104°F) for 30 minutes starting 2 hours before bedtime improved their sleep [
341
]. In this experiment they immersed themselves in water to mid-chest level, but another study showed that heating of feet alone can facilitate falling asleep [
342
]. Healthy women used three conditions: a hot bath, a hot footbath, and no treatment (control). The hot bath consisted of immersion to mid-chest level in hot water at 40°C (104°F) for 20 minutes, starting at 10:10 PM. The hot footbath involved immersing the legs to the knees in hot water (42°C) for 30 minutes, starting at 10:10 PM. The test subjects in both experimental groups fell asleep faster and reported better quality of sleep the next morning compared to the control group of women. Additionally, studies show that placing animals in a warm environment for several weeks increases the amount of time they spend sleeping [
343
]. Even brief exposure of laboratory animals to heat can promote sleep [
344
-
346
]. Excessive heat, however, has the opposite effect [
347
]. Sleep disturbances in humans correlate with hot weather (heat waves). A research team in the Netherlands has conducted a lot of studies on the effects on sleep of various ways of heating and cooling the body [
348
]. Continuous warming of the skin throughout the night by about 0.5°C (~1°F) using a special thermosuit was effective in facilitating falling asleep and improving various characteristics of sleep [
349
,
350
]. The researchers observed this effect both in healthy subjects and in patients with insomnia [
351
]. Mild warming of the skin that excluded the head, hands, and feet had the most pronounced sleep-promoting effect.

If moderate heating of the body promotes sleep, then it should slow down mental processes. One study investigated the effects on mental abilities of a brief exposure to heat (in a hot environment). This treatment slowed reflexes, impaired performance of some mental tasks, and increased fatigue temporarily [
352
]. These data are in line with the results of another group of investigators who have shown that heat reduces information processing speed in soccer players [
924
]. All of the above studies suggest that moderate heating of the body shares some physiological effects with sedative drugs such as benzodiazepines (
Valium
®): they can improve sleep and slow down mental processes. One study shows that during a heat wave, doctors see fewer patients with complaints of anxiety [
353
]. Several other studies report that heating or warming of the body reduces anxiety [
817
,
818
,
894
]. The possible mechanism of the sedative effect of heat may involve increased levels of two sedative chemicals, serotonin and GABA, in the brain.
^M
These biological effects suggest that this treatment should be beneficial in some anxiety disorders,
^M
although nobody has tested this idea in clinical trials, as far as I know. Because of the effects on brain serotonin, repeated daily heating of the body in hot baths or showers may also be beneficial in some depressive disorders.
^M
Immersion in hot water raises the blood level of prolactin [
354
], a hormone that can serve as an indicator of serotonin activity in the brain [
355
]. One report indeed showed that repeated heating reduced depressive symptoms in a group of cancer patients [
356
].

In conclusion,
significant
heating of the body that raises core body temperature by several degrees Centigrade (the condition known as hyperthermia) is not necessary for improvement of sleep. Moderate surface heating will do the job. Moderate heating is also much safer than treatments that cause hyperthermia.

• Moderate heating of the body shares several biological effects with sedative drugs: slowing of reflexes and similar chemical changes in the brain.
  
• Moderate heating increases the level of GABA and serotonin in the brain, the chemicals that have sedative properties.
  
• Several studies on laboratory animals and human subjects show that moderate heating of the body does promote sleep, and therefore you can use this method as a sleeping aid.
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Warning:
Heating the body can adversely interact with some medications and can have adverse effects in some medical conditions, including but not limited to headache, hypotension, inflammatory conditions, and fever. Heat should not be combined with the following medications or substances: alcohol, alpha-andrenergics, amphetamines, anticholinergics, antihistamines, benzodiazepines, beta-blockers, calcium channel blockers, cocaine, diuretics, laxatives, neuroleptics, phenothiazines, thyroid agonists, and tricyclic antidepressants. If you are taking any medication or have a chronic medical condition, you need to consult with your doctor before using hot hydrotherapy. Do not drive or operate machinery after heat-based treatments because they can increase fatigue and slow down mental processes.

Heating the body may be useful for students or knowledge workers who have trouble falling asleep after a disruption, such as jetlag or cramming all night before an exam. There are three convenient ways of heating the body: a warm environment, moderately hot baths, and hot showers that exclude the head. You can use one of these procedures before going to bed (at night). If you use hot hydrotherapy in the morning or in the afternoon, it can disrupt your usual sleep pattern. For example, it can make you sleepy in the afternoon, and if you take an afternoon nap, you may not be able to fall asleep at your usual time at night.

If you have your own room, you can create a warm or moderately hot environment by means of a heater with a built-in fan, or you can use a heater and a separate fan. Depending on the output of your heater, you can increase the air temperature in your room by one to three degrees Centigrade (2 to 6°F) within 20 or 30 minutes. You can start heating the room about 2 hours before going to bed. If you stay in this warm environment during this time, you will start feeling sleepy, which will help you fall asleep. You can either turn off the heater and fan when you go to bed or you can turn down the output and go to sleep with the heater on. You may need to experiment with different parameters of the above procedure to find the conditions that work best for you. The most effective temperature for me is 29°C (84°F) and I can have this air temperature the whole night, although it’s not necessary. I do not use sleep-promoting treatments on a regular basis. But when I have trouble falling asleep, I use one of the warming approaches proposed in this section. An additional layer of clothing (sweater and warm pants) improves heating of the body. Changing the way you dress (or the thickness of your blanket) when you go to sleep is trickier. If you dress too warmly, you may wake up in the middle of the night because you are too hot. An uncomfortably hot environment disrupts sleep, whereas a
moderately
hot or warm environment tends to promote it. Another effect of a hot environment is the lowering of mood [
352
,
651
]. You may start feeling fatigued, apathetic, and pessimistic under these conditions, especially if you put on an extra layer of clothing. This approach may serve as an anti-manic (mood-stabilizing) treatment, and clinical research is needed in this area.

If you can afford a hot tub with automatic regulation of temperature, this is the easiest type of hydrotherapy to help you relax and fall asleep. In a hot tub you can set water temperature to 38-39 degrees Celsius (100.5 to 102°F), turn on the bubbles or jet streams, and sit for 10 to 30 minutes. If you do not have a jacuzzi or hot tub, you can fill your bathtub with hot water at the above temperature. You need a thermometer designed for measuring temperature of liquids (not an air thermometer). Immerse yourself in the hot water up to the neck or mid-chest level and relax for 10 to 15 minutes. You can turn on the radio or put on some relaxing music to make the procedure less boring. The water temperature will drop by about one to two degrees Celsius (2 to 4°F) in 15 minutes. If you want to enjoy the hot bath longer, drain about one-fourth of the volume of water and refill with hot water. Stir the water and make sure the temperature is around 38 to 39 degrees Celsius (100.5 to 102°F). You can then use the hot bath for another 10 to 15 minutes.