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When Nerves Need Verve

Mental energy is a human resource that sometimes seeks an assist.

Patel Kratirov/iStock, Rakicn/iStock
Patel Kratirov/iStock, Rakicn/iStock

Remember the definition of energy from high school physics? The capacity to carry out work. That is also what people mean when they talk about their own energy level.

If you tell your friend you got super-energized by taking a run while listening to a rock song, what you are actually saying is that your capacity for productive output was enhanced for some time after your run.

When you’re full of energy, life feels easy, and it’s easy to stay motivated. General health, sleep status, nutrition, and medication—all influence mental energy.

While physical energy has long been well-defined and measurable, only recently have scientists focused on mental energy. Reporting in Nutritional Neuroscience, Patrick J. O’Connor, of the University of Georgia, and colleagues identified three distinct aspects of mental energy:

  • Cognition, or sustained attention and vigilance, choice-reaction time
  • Motivation, the determination to do mental work and enthusiasm for it
  • Mood, or feelings of having the capacity to complete mental and physical activities, and/or the absence of feelings of fatigue

The three elements of mental energy are measured with cognitive tests; visual analog scales, often used to assay the intensity of moods; and sometimes even brain scans. The visual analog scales give definition to such subjective characteristics as study participants’ mood states. Researchers also measure reaction time and accuracy of performance on cognitive tasks to assess vigilance and fatigue.

Mental energy is important in its own right, but studies show that it also triggers physical energization, fueling efforts to perform physical tasks.

There’s evidence that consuming certain natural substances can increase a person’s mental energy level. Think of the jolt you get from caffeine. The science of agents that can boost mental energy goes far beyond caffeine.

Because the neurotransmitter dopamine is associated with motivation for reward, people often think of dopamine-boosting drugs when it comes to increasing motivation and energy levels pharmacologically. Caffeine, for example, is a dopaminergic drug. Dextroamphetamine, an amphetamine variant often used to treat attention-deficit disorder, and modafinil, a prescription drug developed for the treatment of narcolepsy, are two stimulant agents often used by students to increase their energy level for late-night study sessions. Both drugs exert their energy-boosting effects through dopamine pathways in the central nervous system.

Many stimulants people consume to increase energy are illegal in most countries, but that doesn’t keep their users from trying to get an edge. A 2016 survey of Oxford University students found that 15.6 percent had taken illicit drugs that year to improve their academic performance.

Modafinil and other stimulants do seem to enhance energy levels and motivation the day they are taken. One study found that healthy people who took 300 mg of modafinil experienced improved vigilance and motivation and less fatigue—all three aspects of mental energy—compared with healthy controls who received a placebo.

Many stimulant drugs come with potential psychological side effects that are poorly understood scientifically. For example, modafinil appears to induce overconfidence in one’s own cognitive performance in sleep-deprivation circumstances. Although the drugs may be useful and safe, there is not enough science on the long-term psychological effects to recommend their use.

Although it’s far from invariable, there’s some evidence that substances that occur naturally in foods and in the human body are safer than man-made drugs. As substances we’ve evolved in tandem with, they are likely to be handled relatively well by our system. When taken in the form of a supplement, they can boost energy levels.

Coenzyme Q10 (CoQ10) is an antioxidant naturally present in the human body and in many foods. It plays a role in cellular energy production and antioxidant defense of tissue. Studies show it particularly protects the heart and blood vessels. It is found in high amounts (30mg/serving) in organ meats.

CoQ10 exists naturally in different variations, ubiquinol being the best-absorbed and most-studied form of this ergogenic substance. In daily doses of 100 mg and 150 mg for 12 weeks, it has been found effective for increasing motivation and mental energy levels compared with a placebo.

CoQ10 also significantly reduces subjective fatigue, objectively measured fatigue, and subjective sleepiness after demanding cognitive tasks. The greater the blood level of CoQ10, researchers have found, the greater the effect on maintaining mental energy and reducing mental fatigue.

Of all the micronutrients supplied by food, vitamin B12, or cobalamin, ranks as one of the most important for brain function. It takes only a tiny amount to avert a deficiency, but vegetarians and vegans are at special risk. So are the elderly, as consumption and absorption often decline with age. Studies show that neurological deficits can occur even in the presence of “normal” blood levels.

Several large-scale surveys indicate that around 3 percent of the population in developed countries is deficient in vitamin B12, but that may be an undercount as scientists are gathering evidence that current recommended blood levels for the vitamin are set too low. Even low-normal levels of vitamin B12 increase the risk for cognitive impairment, mental fatigue, neuropathy, and anemia in the elderly.

Both CoQ10 and vitamin B12 can help people safely maintain high energy levels throughout the workday. Vitamin B12 confers its benefits primarily on those who are marginally or frankly deficient in the vitamin. CoQ10, on the other hand, appears effective for people whether or not they have a clinically diagnosable deficiency of the nutrient.

Stay tuned. The science of mental energy boosters is just getting started.

Energy Bites

  • However elusive the mood facet of mental energy may seem, researchers find it has real economic value—it underlies work productivity.
  • Caffeine is the world’s most common mental energizer.
  • Caffeine increases dopamine receptor activity in the human brain; the enhanced dopamine signaling mediates an increase in alertness.
  • Three out of 10 people who use dietary supplements do so to increase mental energy.
  • Coenzyme Q10 enhances activity of the autonomic nervous system.
  • Approximately 15 percent of U.S. college students take ”study drugs,” such as amphetamines, nonmedically to boost mental energy when preparing for exams.
  • Created by bacteria, vitamin B12 is available only from animal products.
  • Vitamin B12 does not act alone; evidence indicates that adequate levels of all the B vitamins are needed for any one to confer optimal brain function.