1. Vitamin E May Support Proper Brain Function

According to Harvard Health Publishing, there is good scientific evidence that Vitamin E can help to slow mental decline in patients with dementia or Alzheimer's disease. Unfortunately, the study that produced that evidence used a Vitamin E dose much higher than the typical recommended daily allowance.

Nevertheless, it is possible that a diet rich in Vitamin E can support proper brain function. Foods rich in Vitamin E include almonds, hazelnuts, peanuts, spinach, sunflower seeds and broccoli.

2. CBD May Combat Test Anxiety

Cannabidiol – a THC-free extract sourced from industrial hemp plants – is a dietary supplement that has become increasingly popular among people looking for safe treatments for a variety of different conditions. Research into the properties of CBD is still ongoing, but early results – such as a 2015 study published in "Neurotherapeutics" – suggest that CBD holds potential as a treatment for anxiety disorders.

Do you suffer from frequent test anxiety? A CBD supplement from a company such as OK CBD could help. Unlike other anxiolytic agents such as kava, CBD doesn't induce drowsiness and won't put you to sleep during your study sessions.

3. Ginkgo Biloba And Panax Ginseng Are Staples Of Traditional Chinese Medicine

Ginkgo biloba is a tree that has been grown for medicinal and food purposes for hundreds of years. Ginkgo and panax ginseng are important ingredients in traditional Chinese medicine, and they are often taken together or separately to support mental acuity.

The good news is that ginkgo and ginseng have hundreds of years of use to support the idea that they're helpful for brain functioning. The bad news is that no clinical trial has ever verified that claim. Nevertheless, you may find it worthwhile to try the supplements and see how they work for you.

4. Fish Oil Supplies The Brain With Essential Fats

Obtained from the processing of fatty fish such as shark, cod and tuna, fish oil is rich in the fatty acids DHA and EPA and may help to improve mental functioning by reducing inflammation and supplementing the omega-3 fats that the brain requires. Studies suggest that DHA and EPA supplementation may improve brain development; the two fatty acids appear to improve concentration and attention in children.

However, studies also suggest that DHA and EPA do not slow the rate of cognitive decline in older individuals – so your mileage may vary. If you do decide to take a fish oil supplement, choose a supplement with DHA and EPA content verified by an outside laboratory. Remember that oil taken from predatory fish may contain higher than acceptable levels of toxic substances such as mercury.

Are you a vegetarian? No problem; take an algal oil supplement instead. Algal oil is rich in both DHA and EPA.

5. Ashwagandha May Reduce Stress Levels

The powdered root of Indian ginseng – also known as ashwagandha – has been used for centuries in traditional Indian medicine to increase energy by helping the body combat the effects of stress. Does it work? To date, no clinical trial has supported the effectiveness of ashwagandha for treating any condition.

In non-clinical studies, however, participants taking ashwagandha have shown marked improvements in their fatigue, stress and anxiety levels. Ashwagandha may also improve energy levels by combating physical stress. A study that examined the effects of ashwagandha on bicycle riders found that those taking the supplement improved their cycling endurance by 7 percent.

6. Coenzyme Q10 May Improve Alertness

Coenzyme Q10 (COQ 10) is a substance found in cells throughout the human body. It's a necessary part of the cellular respiration process and helps the body generate its energy. Owing to its importance within the human body, you can find COQ 10 as a supplement in virtually every health food store.

Although COQ 10 is necessary for proper cell functioning, there is no clinical evidence that COQ 10 improves health or combats any condition when taken as a dietary supplement. If your body doesn't contain the correct amount of COQ 10 already, though, non-clinical trials suggest that the supplement may improve your energy levels and help you stay alert.

7. Vitamin B12 May Reduce Fatigue And Improve Concentration

Vitamin B12 is yet another vitamin that's essential for proper functioning. If you aren't getting enough Vitamin B12, you may feel fatigued and have difficulty concentrating. The good news is that if you eat meat, eggs and dairy products, you're probably getting enough Vitamin B12 already. Some vegetarians and vegans, however, are deficient in the vitamin. Many vegan products – such as non-dairy milks – are fortified with Vitamin B12. Nutritional yeast is also an excellent vegan source of the vitamin.

8. Iron May Enrich The Brain's Blood Supply

Without iron, your body can't make red blood cells. Without those cells, your brain may be starved of its supply of iron-rich blood – and your ability to stay awake and concentrate during lengthy study sessions may be compromised. If you're an omnivore, you're probably already getting plenty of iron from the meat that you eat and have no reason to begin taking a supplement.

If you're a vegetarian, though, it's wise to eat iron-rich foods such as beans and fortified bread, pasta and cereal. You'll find that most grain products that aren't organic are fortified with iron.

9. Beet Powder May Increase The Brain's Blood Supply

Here's a supplement for studying that you might not have thought of. Beets contain nitrate – the same substance that some older people take to relieve chest pains. The reason why nitrate reduces chest pain is that it opens the blood vessels and improves circulation. Increasing the amount of blood that gets to the brain can improve your mental functioning, and the easiest way to do that is by taking a powdered beet supplement.