Written by Slawomir (“Swavak”) Gromadzki, MPH

Serotonin is another hormone found in the intestines and the central nervous system. It is a very important neurotransmitter which controls numerous functions in our organism including appetite, metabolism, emotions, mood, memory, sleep, or sexual desires. It was estimated that between 60 to even 80 percent of people living in America, especially women, have low levels of this hormone. It makes us feel less anxious, more peaceful and at the same time more energetic. When we have enough serotonin we can feel satisfied even if our stomach is not yet full. As a result we tend to eat less and lose weight.

We know that serotonin is very important in fighting obesity, depression, fatigue, or insomnia. Serotonin is the feel good hormone and neurotransmitter which helps us regulate moods and use good judgment. Unfortunately, the older we get the less serotonin we tend to produce. Dr. Carolyn Meltzer’s research has demonstrated that with age serotonin receptors decrease by over 50%. People who struggle with overweight, obesity, and depression, those who commit serious crime as well as people who commit suicide have very low level of this extremely important hormone.

Normally, serotonin activates some neurons and receptors to reduce appetite and at the same time it has ability to block other neurons which increase appetite. Appetite is stimulated by the hormone dopamine but, as you eat, serotonin is released in order to stop the influence of dopamine. Unfortunately, if you don’t have enough of serotonin or when the number of serotonin receptors is low then it leads to overeating and weight gain. According to the research conducted by International Journal of Obesity in 2010, animals with low level of serotonin in the brain easily develop obesity.

Serotonin deficiency can be caused by sedentary lifestyle (lack of physical activity), insufficient light during the day, refined and low in nutrients diet, use of stimulants (alcohol, nicotine, coffee, tea, cola drinks, chocolate, and other caffeine products), insufficient amount of sleep, and medications.

In the book ‘The Natural Way to Overcome Depression, Obesity, and Insomnia’ Dr. Michael Murray wrote: “Bad diet, lack of exercise, use of harmful substances such as alcohol or caffeine (coffee, chocolate, tea, cola drinks, etc.) can rob your brain of the ability to make enough serotonin. This produces a range of significant complications: depression, obesity, insomnia, migraine headaches, or chronic fatigue.” It means that in order to have more serotonin you have to exercise and avoid stimulants such as alcohol and foods or drinks which contain caffeine (coffee, chocolate, tea, cola drinks, etc.).

In January 2009 Psychopharmacology reported that one of the studies found that also stress greatly decreases serotonin levels.

If you want to have enough serotonin you should stay away from the low-calorie diets as experiments with rats demonstrated that reducing calories in their diet decreased serotonin levels. Instead, follow the normal-calorie unrefined plant-based diet presented here which is the best, most healthy, and effective way to elevate serotonin levels in the body.

Animal studies have shown that low levels of serotonin were associated with impulsive, aggressive and risky behaviours. According to the Society for Neuroscience, monkeys who had lower levels of serotonin were willing to take risky jumps from the trees and injured themselves, while those with normal serotonin level used good judgment. Likewise, if you don’t have enough of this hormone you will have tendencies to make unwise decisions including foolish nutritional choices. Without serotonin you will be willing to eat junk food in spite of consequences such as gaining weight or you might even decide to take the risk of suffering and loosing life as a result of heart attack, stroke or cancer caused by choosing an unhealthy lifestyle and diet.

Lack of serotonin is also responsible for impulsive behaviours or inability to delay gratification (wait patiently for a better reward). Rats with lower serotonin levels tend to behave in a risky way, and instead of waiting for a better reward prefer to accept small ones immediately. Again it proves that without serotonin it would be very difficult for you to keep your promises and resolutions, and keep on living according to the principles of healthy diet and lifestyle in order to get rewarded with good health or fit and slim body.

The researchers also examined the levels of serotonin of many different people and it turned out that prisoners who had committed murder had abnormally low levels of this hormone. There is also a lot of evidence showing that low serotonin level is associated with depression and suicidal thoughts as people who commit suicide have very low levels of this hormone. In addition, it was discovered that before committing suicide they had tendencies to overeat and demonstrated impulsive behaviours.

Since depression is often related to the inability to use serotonin physicians prescribe medications for depression called Selective Serotonin Reuptake Inhibitors (SSRIs) which are supposed to help this neurotransmitter to do its job more efficiently. As a result patients who use such drugs report feeling better but at the same time experience some negative side-effects such as weight gain, insomnia, restlessness, sexual problems, nausea, diarrhoea, etc. Besides, although anti-depressants tend to increase the ability of our body to use serotonin more efficiently and even restore the serotonin we already have, yet usually they don’t increase the amount of this neurotransmitter.

Fortunately there are some natural ways you can use to have more of this precious hormone. According to Harvard psychiatrist Joseph Glenmullen serotonin can be enhanced by positive thinking, stress control, and by aerobic exercise such as brisk walking. Exercise can raise serotonin levels by both increasing the synthesis and release of it.

According to Dr. Sang Lee even looking at certain colours such as blue or green can positively affect serotonin levels. That is why staring at the green colour of grass or trees and blue colour of the sky, ocean, lake, river, or even a swimming pool water may raise serotonin. Knowing this we can understand why the surrounding us nature is dominated by these two colours. Our loving Creator gave us so much blue and green colours in order to boost good hormones, soothe our nervous system and to energize us at the same time during the day stimulating our metabolism.

Have you ever seen a vast field of sunflowers wondering why they looked like an army of soldiers with heads turned toward the same direction? One scientist decided to check which of the colours of the sunlight makes sunflowers to follow the sun all day long. And only when he removed the blue colour from the spectrum the sunflowers stopped moving! The visible light such as sunlight looks white in colour, but if we could separate this light into its parts, we would see a rainbow of different colours. Red, Orange, Yellow, Green, and Blue are the colours from weakest to strongest energy. Therefore, the red light has the largest wavelength and weakest energy, while the blue light has the smallest wavelength and strongest energy. It means that sunflowers follow the blue light because it has the shortest and at the same time the most stimulating and energizing them waves! The blue light stimulates their growth! That is also the reason why when we go for a walk and have contact with nature seeing the beautiful blue color of the sky and allowing the sunshine to influence us with its blue light we have more energy and feel happier because the serotonin level gets higher. When we see the blue and green colours it is as if God himself wanted to tell us, “Live! Be happy and active!” Unfortunately, without regular physical activity during the day and contact with nature, the sunlight, and the blue or green colours, we have low levels of serotonin which in turn makes us depressed, nervous, weak, and unable to control appetite.

The very opposite to the blue and green colour is the red and yellow light which are the longest and thus the weakest types of light. That is why in the past photographers used red light in their darkrooms. The light was so weak that it was unable to expose even the very sensitive to light photographic paper. Knowing this we can easily draw a conclusion that also when the sun is setting it is not a coincidence that we often see a lot of the beautiful red and yellow colours which have the longest and therefore the weakest waves. As the day is getting to an end our wise and caring Creator ‘painted’ beautiful sunsets with red and yellow colours because through them He wants to tell us, “It is time to stop working. Now you can rest and go to sleep”. But, unfortunately, also in this case, instead of obeying this delicate and quiet voice (like chicken that go to sleep after sunset), the great majority of intelligent human beings prefer to violate their natural needs. Instead of going to sleep they force their tired mind and body to keep working at night and ‘whip’ their brains with coffee, tea, cola drinks, chocolate, alcohol or other stimulants so that they could spend more time in front of a computer or TV. As a result they start experiencing different health problems, and as soon as they develop cardiovascular diseases, mental disorders, cancer, autoimmune diseases, obesity or other serious health-related disorders they tend to ask silly questions such as, ‘why me God?’

How true, therefore, are the words written over one hundred years ago in the book “Ministry of Healing” by Ellen White – the popular American writer and propagator of healthy lifestyle: “The sick, shut within four walls, look out on houses and pavements, with perhaps not even a glimpse of blue sky or sunshine, of grass or flower or tree. Shut up in this way, they brood over their suffering and sorrow, and become a prey to their own sad thoughts. The pure air, the glad sunshine, the flowers and trees, and outdoor exercise amid these surroundings, are health- and life-giving. Outdoor life is the only remedy that many need. It has a wonderful power to heal diseases caused by the excitements and excesses of fashionable life, a life that weakens and destroys the powers of body, mind, and soul. How glad would they be to sit in the open air, rejoice in the sunshine, and breathe the fragrance of tree and flower! There are life-giving properties in the balsam of the pine, in the fragrance of the cedar and the fir, and other trees also have properties that are health restoring… In nature may always be found something to divert the attention of the sick from themselves and direct their thoughts to God. The beauty of nature leads them to think of the heavenly home, where there will be nothing to mar the loveliness, nothing to taint or destroy, nothing to cause disease or death”.

It is now a well-documented scientific fact that it is the lack of light (especially during winter season) which is responsible for causing a popular form of depression called SAD (Seasonal Affective Disorder) that occurs at the same time every year. For this reason light therapy is used in this case with excellent results. That is why in the northern areas of the United States significantly more people suffer from depression than in the southern and sunny states.

In one interesting experiment scientists asked patients with depression to wake up early in the morning at 5 am, go out and expose themselves to the sunlight. As a result the symptoms of depression disappeared. They also demonstrated that the early morning sunlight was the most effective in fighting depression. However, in order to wake up early in the morning you also need to go to bad before 10pm.

It was demonstrated that the full-spectrum light stimulated chickens to release serotonin so well that they lived twice as long! In addition to that, they were also calmer and produced eggs which were much lower in cholesterol! That is why also when we wisely expose our body to the sunlight we feel more relaxed, have stronger immune system, and have lower blood cholesterol.

It was reported that the non-full-spectrum lighting, which is often used in work places and our homes, has created stressful amounts of hormones such as cortisol and ACTH. On the other hand, the artificial full spectrum lighting, which imitates the natural light found in sunlight, can significantly improve our mood and energy level.

Some experts, however, conclude that it is not the type of light but rather its intensity which is more important as the therapeutic value comes from the brightness of the light. They seem to agree that the full spectrum light is healthier but they suggest that at the same time any bright light therapy helps to decrease the symptoms of SAD, PMS, heart rhythm disorders, insomnia, or fibromyalgia, and help to cope with obesity through elevating the serotonin levels.

Unfortunately, for therapeutic purposes we need very bright light of at least 2,500 lux. The stronger the light the better results can be achieved. That is why it is so important to go for a walk and use benefits of the natural sunlight any time the weather is fine because in a full daylight even without direct sun the strength of light is 10,00025,000 lux, while in direct sunlight it is 32,000130,000 lux! Even on a cloudy day we have about 1,000 lux of light available. Unfortunately, the artificial light we have at home or work is usually only between 50 to 150 lux.

Another very important way of increasing serotonin level in our body is diet rich in amino acid tryptophan which is converted to serotonin in the brain. Dr. Agatha Thrash in her book “Food Allergies” states that, “Foods with low content of tryptophan may negatively affect the levels of serotonin thus leading to depression”. According to the study published in the Archives of General Psychiatry, women with a history of bulimia nervosa, experienced relapses of this eating disorder as a result of consuming an amino acid mixture which was deprived of tryptophan.

There is a myth that plant protein does not contain significant amounts of tryptophan. The opposite is true as tryptophan is present in almost all forms of plant protein. The highest amount of tryptophan is found in cooked soya beans and Tofu (soya cheese). Another excellent source is Tahini (sesame butter) and Halva which is very tasty and sweet. Apart from ground sesame seeds Halva may contain different sweeteners such as honey or sugar. However, in health food shops you can also find Halva sweetened with grape juice, which seems to be a better choice. Although Tahini and Halva are not higher in tryptophan as soya beans and Tofu yet the ratio between tryptophan and other amino acids found in these two products is most beneficial and for this reason they are regarded as one of the best sources of tryptophan. All the following plant foods are either excellent sources of this important amino acid or effectively help our body to produce it: All pulses or legumes (beans, chickpeas, lentils, etc.), Spirulina, brown rice, avocados, oats, tomatoes, kiwis, plums, fresh pineapples, eggplant, bananas, seeds and nuts (especially sesame seeds, pumpkin seeds, peanuts, sunflower seeds, and walnuts), dried fruits (raisins, dates, figs). Also chia seeds, which are known to be the best source of omega 3, contain more than twice the amount of tryptophan found in turkey, which means they are very helpful in increasing the levels of serotonin in our body.

It is very important to remember that sufficient amounts of vitamin C, B3, B6 (pyridoxine), folate, zinc, and magnesium are necessary for the formation of tryptophan, which, in turn, is necessary in your body for the formation of serotonin. Apart from that, it has been shown that magnesium, vitamin B6 and B3 can also assist conversion of tryptophan to serotonin. For this reason our diet should be high in those nutrients and for the best results good quality supplements can be used.

It is true that tryptophan is also found in animal foods especially milk, but animal sources (including milk and dairy) are much higher in other competitive amino acids thus hindering absorption of tryptophan. In addition, milk also contains numerous high-risk factors such as cholesterol, triglycerides, antibiotics, dioxins and may be contaminated with extremely dangerous and deadly prions or leukemia virus which are able to survive the pasteurization and cooking process.

Study by Professor J. Wurtman (2009) demonstrated that tryptophan, which is the building block of serotonin, can get into our brains only when sweet unrefined carbohydrates are consumed. Thus, more serotonin is made after you consume sweet unrefined carbohydrates such as fruits (especially bananas and dried fruits). According to Wurtman carbohydrates eaten in the beginning of the meal were effective in reducing hunger.

However, because tryptophan is an amino acid (protein), therefore a diet rich in other types of protein (meat and dairy products) greatly hinders tryptophan from passing from the blood to your brain. It is so because tryptophan has to compete with many other amino acids (proteins) while trying to enter the brain and as a result only small amount of this important amino acid gets in. That is another reason why you should be on the plant-based and unrefined diet. It is not only rich in tryptophan, which is essential to produce serotonin, but at the same time, unlike the animal-based diet, it is not too high in protein, and also gives you opportunity to eat unrefined sweet carbohydrates which are necessary to allow tryptophan to reach brain where it is converted to serotonin thus helping you to control appetite and negative emotions.

Numerous studies have demonstrated that the amino acid 5-HTP (5-Hydroxy L-Tryptophan), which is made from tryptophan, and that in turn is used by the body to produce serotonin is helpful in coping with obesity, insomnia, anxiety, and depression. Researchers found that people using the 5-HTP had significantly greater levels of satiety (they felt more full after consuming their meals) than the control group. The 5-HTP group also had greater decrease in hip circumference and lower BMI (body mass index) than the control group. 5-HTP is also regarded as a potent antioxidant able to protect the body against the free-radical damage, thus reducing the risk of numerous health problems such as cardiovascular diseases, fatigue, cancer, etc.

When humans and animals are fed tryptophan-free diets, appetite is significantly increased, resulting in binge eating. A diet which is low in tryptophan leads to serotonin deficiency because our brain interprets lack of tryptophan as a result of starvation and therefore it stimulates the appetite. This stimulation results in a preference for carbohydrates and craving for a sweet foods. Unfortunately, most people choose products high in refined sugar instead of complex carbohydrates (fresh and dried fruits).

In 1989, the U.S. Centers for Disease Control reported evidence linking L-tryptophan supplements to a disorder characterized by an elevated white blood cell count. However, subsequent research showed that it was contaminants in the supplements, not the tryptophan, that was responsible for the problem.




Lam, D. D., Garfield, A. S., Marston, O. J., Shaw, J., and Heisler, L. K. Brain serotonin system in the coordination of food intake and body weight. Pharmacology, Biochemistry and Behavior. 2010;97(1):8491

Meltzer CC, Smith G, Price JC, et al. 1998. Reduced binding of [18F] altanserin to serotonin type 2A receptors in aging: persistence of effect after partial volume correction. Brain Res 1998; 813: 167-171.

Li D, He L. Meta-analysis supports association between serotonin transporter (5-HTT) and suicidal behavior. Mol Psychiatry 2006; 12:47-54.

N Uceyler, M Schütt, F Palm, et al (2010) Lack of the serotonin transporter in mice reduces locomotor activity and leads to gender-dependent late onset obesity. International Journal of Obesity (2010) 34, 701711.

Michael T. Murray (1998). 5-HTP: The Natural Way to Boost Serotonin and Overcome Depression, Obesity, and Insomnia. June 1st 1998 Bantam.

Hirsch M, et al. Unipolar depression in adults and selective serotonin reuptake inhibitors (SSRIs): Pharmacology, administration and side effects. www.uptodate.com/home. Accessed June 5, 2013.

Sargent, B. J., and Moore, N. A. New central targets for the treatment of obesity. Br J Clin Pharmacol. 2009; 68 (6): 85260.

“Leptin-Serotonin Pathway Offers New Clues For Obesity And Osteoporosis Prevention.” Medical News Today. (2009, September 5).

Joseph E. Pizzorno Jr & Michael T. Murray. The Textbook of Natural Medicine. Second Edition. Volume 1. 1999.

Int J Neurosci. 1992 Nov-Dec; 67(1-4):127-44.

Breum L, Rasmussen MH, Hilsted J, Fernstrom JD. Twenty-four-hour plasma tryptophan concentrations and ratios are below normal in obese subjects and are not normalized by substantial weight reduction. The American journal of clinical nutrition. May 2003; 77(5):1112-1118.

Cangiano C, et al. Effects of oral 5-hydroxy-tryptophan on energy intake and macronutrient selection in non-insulin dependent diabetic patients. Int J Obes Relat Metab Disord. 1998; 22:648-654.

Cangiano C, Ceci F, Cascino A, et al. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. J Clin Nutr. 1992; 56: 863-867.

Young SN (2007). “How to increase serotonin in the human brain without drugs”. J Psychiatry Neurosci 32 (6): 3949. PMC 2077351. PMID 18043762.

Hales, S.E.; Hales, C.N. (2004). “Lifespan: catch-up growth and obesity in male mice”. Nature. 427 (6973): 4112. Bibcode: 2004Natur. 427. 411O.

Martinez A, Knappskog PM, Haavik J. A structural approach into human tryptophan hydroxylase and its implications for the regulation of serotonin biosynthesis. Curr Med Chem 2001 Jul; 8(9): 1077-91. 2001. PMID: 15980.

Moore P, Landolt HP, Seifritz E, et al. Clinical and physiological consequences of rapid tryptophan depletion. Neuropsychopharmacology 2000 Dec; 23(6): 601-22. 2000. PMID: 16020.

Joseph Mercola, Light Therapy Promising for Treating Major Depression, January 26, 2011:

http://articles.mercola.com/sites/articles/archive/2011/01/26/light-therapy-promising-for-treating-major-depression.aspx |

University Of Pennsylvania School Of Medicine (2005, July 11). Mood Lighting: Penn Researchers Determine Role Of Serotonin In Modulating.

Taking Antidepressants: Your Comprehensive Guide to Starting, Staying On, and Safely Quitting, by Michael D. Banov, M.D. (Sunrise River Press, 2010).

The Antidepressant Solution: A Step-by-Step Guide to Safely Overcoming Antidepressant Withdrawal, Dependence, and “Addiction,” by Joseph Glenmullen, M.D. (Free Press, 2006).

Curr Opin Neurobiol. 2013 Feb 2. pii: S0959-4388 (13) 00027-5.

Prog Neurobiol. 2000 Jan; 60(1):13-35.

J Nutr. 2012 Dec; 142(12):2236S-2244S.

J Exp Biol. 2002 Dec; 205(Pt 23):3679-87.