HOW THE FOODS WE EAT AFFECT OUR MENTAL HEALTH
- October 10, 2016
A discipline called ‘nutritional psychiatry’ has emerged over the past few years, with a strong focus on the role of nutrition when it comes to mental health issues – something that’s often largely ignored but has remarkable implications. 1, 2 For instance, researchers have observed the increased prevalence of mental health disorders in correlation with the Western diet’s nutritional deterioration.3
As part of World Mental Health Day’s initiative to drive a better understanding of mental health disorders, it’s time we also became more aware of how everyday foods affect our mental health.
Our body needs certain nutrients in order to build ‘neurotransmitters’, which are chemical messengers that facilitate the transmission of electrical signals in our brain (as with the rest of our body). When this process doesn’t take place properly, mental illnesses like depression, hyperactivity and bipolar disorder can ensue. It logically follows that consuming neurotransmitter-building nutrients could improve the functioning of these electrical signals, in turn promoting mental health.
Even the foods that increase levels of our body’s feel-good hormones like serotonin, dopamine, endorphins etc., could reduce symptoms of mental health issues that are deep-rooted in anxiety, distress and depression.
While we, as always in our posts, reiterate the importance of getting as wide a range of nutrients into one’s regular meals as possible, the following list of foods can specifically improve one’s mental health.
1] Protein-rich Foods
The building blocks of proteins are called amino acids that, in addition to their most well-known functions of building lean muscle and our hair and skin tissue, also build neurotransmitters and hormones. For instance, tryptophan is an amino acid that’s used by the body in the production of serotonin, a feel-good chemical, while an amino acid called taurine is known to elicit a calming effect on the brain.3,4
A good way to try and make sure one is getting enough protein is to try and get at least <0.8> multiplied by worth of protein (in grams) a day (those who exercise regularly can replace 0.8 by 1.2 in this calculation).4
Protein-rich foods include meat, fish, tofu, cheese, beans, lentils, yogurt, eggs, nuts, and seeds.
2] Omega-3 Fatty Acids
It’s been discovered that a nutritional deficiency of omega-3 fatty acids is the most common one correlated to mental disorders like bipolar disorder.5 This would make sense, considering the fact that the ‘long-chain’ form of omega-3 fats, called DHA, helps build neurotransmitters as well as some structures of the brain.
Supplementing our diet with DHA and another omega-3 fatty acid called EPA is associated with an elevated mood and reduced symptoms of depression, and has been shown to improve our resistance to stress.6
These fats are found in fish, flaxseed oil, chia seeds, and walnuts.
3] Fibre-rich and Probiotic Foods
Carbohydrates are the most controversial of all the macronutrients – many believe that they should be steered cleared of as far as possible, while others credit them with having several nutritional benefits in moderation.
Speaking in terms of our mental health, however, the carbohydrate-rich foods that are also nutrient rich do provide us with the building blocks of some neutrotransmitters.
The fibre from these foods also helps the good bacteria in our gut flourish, in what’s known as a ‘prebiotic’ property. Similarly, eating ‘probiotic foods’, i.e., foods that contain good bacteria like yogurt and some pickles (that aren’t brined in vinegar) would also boost the number of good bacteria in our gut.
While that may not seem relevant at first, the gut bacteria actually seem to have an impact on our health, including that of the brain, because of a give-and-take relationship they seem to share with our body; they modulate many functions in exchange for living there.
One intriguing example is the direct connection between the gut, brain and skin, a phenomenon called the Gut-Brain-Skin Axis. Researchers believe that when the gut’s good bacteria are in low numbers, they can’t continue to stop the toxins (coming from the food we eat) from being released into our blood; these toxins then travel to the skin as well as the brain where they create problems like anxiety, stress and depression.7, 8
Even apart from this theory, our mood can be directly affected by our gut– almost 90-95% of the feel-good hormone serotonin is produced in the gut, a process that the good bacteria play a significant role in. The gut is now, in fact, being considered a sensory organ that sends messages to the brain through its enormous nervous system.9, 10
Our stance on the carbohydrates controversy is, for all these reasons, very clear: whole grains, fruits and vegetables are forms of carbohydrates that shouldn’t be ignored.
5] Vitamins and Minerals
Seafood, liver, whole grains and vegetables, especially dark green leafy ones, are all great sources of the B-vitamins.
These vitamins are involved in almost every function of the human body, with B2, B6, B9 (folate) and B12 being important for the normal functioning of the brain and nervous system.2, 11 This includes playing a role in producing neurotransmitters and hormones, and the insulating sheath that’s around nerves. Deficiencies in the B-vitamins are known to affect the mood and other brain functions to a very large extent.12 For example, patients suffering from depression have shown 25% lower levels of folate on average.13 Some studies also indicate that vitamin B12 can delay the onset of signs of dementia.14
Even deficiencies in vitamin D, calcium, chromium, selenium, iodine, and iron have been linked to mental health problems.15
A class of medicines called SSRI that increase one’s levels of serotonin to treat depression, obsessive-compulsive disorder, or any other mental issue, tend to lower the amount of calcium taken up by our bones, putting one at a risk for fractures.16 Getting enough calcium, or discussing this with a doctor, would be a good idea for anyone who’s been prescribed these medicines.
A well-balanced diet can give us all these nutrients, but supplementation is also an option for those who suffer from any specific deficiency.
While we’ve thus far covered the kind of nutrients that we should get plenty of, it’s also important to highlight what to avoid: specifically refined carbohydrates.
In this form, carbohydrates when consumed are rapidly converted into blood glucose, which leads to a surge of glucose in the blood. This spike forces our body to produce a lot of the hormone insulin, to let cells use up the glucose for energy, and thus lower our blood glucose – but too much insulin can compromise the other bodily processes that the hormone is involved in. Over time, this is believed to lead to hormonal and chemical imbalances in the brain.17, 18
The incidence of mental health problems (like depression) has been correlated to the use of refined carbohydrates, either because of this very blood glucose surge, or because these carbs are believed to create an imbalance between our gut’s good and bad bacteria, or because of both.17, 18
That would explain why obese individuals (or those with metabolic problems like diabetes) have been shown to have a higher risk of depression – indeed, the impairment of cognitive function in both conditions is similar.17
A study even showed a highly consistent correlation between the increased consumption of refined sugar, and the worsened condition of schizophrenic patients (measured by social functioning and number of days spent in the hospital). The study reported that this association was as strong as that between diabetes and heart disease.3, 11
All evidence points towards the intricate link between nutrition and mental health issues. While we keep an eye on any updates in the world of nutritional psychiatry, the information that’s already available to us is convincing enough to provide the right nutrition to anyone who has a mental health disorder.
Let’s remember to be more supportive, this World Mental Health Day, in more ways than one.
1. Selhub E. Nutritional psychiatry: Your brain on food. Harvard Health Publications. 2015 16 November 2015.
2. Rao TSS, et al. Indian Journal of Psychiatry 2008, 50(2): 77-82.
3. Lakhan SE, Vieira KF. Nutrition Journal 2008, 7: 2-2.
4. Martens EA, Westerterp-Plantenga MS. Current Opinion in Clinical Nutrition & Metabolic Care 2014, 17(1): 75-79.
5. Osher Y, et al. J Clin Psychiatry 2005, 66(6): 726-729.
6. Kidd PM. Altern Med Rev 2007, 12(3): 207-227.
7. Schmidt K, et al. Psychopharmacology 2015, 232(10): 1793-1801
8. Foster JA, McVey Neufeld K-A. Trends in Neurosciences 2013, 36(5): 305-312.
9. Camilleri M. Current opinion in endocrinology, diabetes, and obesity 2009, 16(1): 53-59.
10. Yano JM, et al. Cell, 161(2): 264-276.
11. Benton D, et al. Neuropsychobiology 1995, 32(2): 98-105.
12. Coppen A, Bolander-Gouaille C. J Psychopharmacol 2005, 19(1): 59-65.
13. Coppen A, Bailey J. J Affect Disord 2000, 60(2): 121-130.
14. Bourre JM. J Nutr Health Aging 2006, 10(5): 377-385.
15. Bertone-Johnson ER. Nutrition reviews 2009, 67(8): 481-492.
16. Richards JB, et al. Arch Intern Med 2007, 167(2): 188-194.
17. Gangwisch JE, et al. The American Journal of Clinical Nutrition 2015.
18. Numakawa T, et al. Frontiers in Psychiatry 2014, 5: 136.