The link between Zinc, Tryptophan and eating disorders

Changes in the diet impact your body and mental health because how you think and feel is directly affected by the foods you eat. Our brain and body are made from food, air and water molecules. An inadequate diet can lead to mood disorders such as depression or anxiety, fatigue, and impaired decision-making. In addition, it can slow down reaction time. Still, the idea that nutrition or malnutrition could play a part in developing and treating eating disorders did not come until the 1980s when scientists realized how similar anorexia nervosa and zinc deficiency symptoms were (see table 1).

This article will find the link between Zinc, Typthophan and eating disorders.

Let’s get started!


Zinc is the most commonly deficient mineral and a critical nutrient for mental health. In addition to anorexia nervosa, many neurological disorders are linked to zinc deficiency, including depression and schizophrenia.

Anorexia Zinc
Weight lossWeight loss
Loss of appetiteLoss of appetite
Amenorrhoea Amenorrhoea
Impotence in malesImpotence in males
Skin lesionsSkin lesions
Anxiety Anxiety
Risk Factors
Females under 25Females under 25
Stress Stress
Table 1

As you can see in the table above, a significant number of the symptoms of zinc deficiency bear a substantial similarity to symptoms of anorexia nervosa. This has inspired many researchers to delve deeper into using zinc supplements as a treatment for anorexia. Unfortunately, zinc deficiency is not uncommon, and because our body doesn’t naturally produce zinc, you must obtain it through food or supplements. Zinc is found in various foods, including meat, fish, nuts, and other dietary sources. People who eat animal protein are more likely to be able to absorb zinc, so vegetarians and vegans are at greater risk of zinc deficiency. But guess what? People with an eating disorder often choose to become vegetarian or vegan, which makes the issue even more challenging to solve since people who eat mainly grains and legumes need more zinc than those who eat meat.

Zinc deficiency may be one of the earliest predictors of anorexia nervosa. However, it is essential to mention that zinc supplements in the treatment of Anorexia nervosa; represent only one factor of this complex disorder.


Tryptophan is an essential amino acid and the building block of melatonin, which helps regulate sleep patterns and serotonin, the brain’s “happy neurotransmitter” that controls mood, behaviour, mental health, appetite, and more. Unfortunately, the body can’t produce it, so as with zinc, it must come from your diet, but because few foods contain high amounts of tryptophan, it is one of the first nutrients you can lose when you start dieting.

When our serotonin levels drop, so do our feelings of self-esteem; on the contrary, our hunger levels go skyrocket, a tricky combination for anyone but especially for these suffering from an eating disorder. For example, in several studies, bulimics were deprived of the single amino acid tryptophan. In reaction, their serotonin levels dropped, and they binged more violently. Also, women with low serotonine levels are likely to have PMS symptoms two weeks before the bleeding, triggering more cravings and low mood.

A study of 20 women showed that those with bulimia nervosa consumed more calories (39% more) and showed mood irritability due to tryptophan depletion. These results indicate that women with bulimia nervosa have an exaggerated response to short-term alterations in serotonin activity and are more prone to tryptophan deficiency. Furthermore, starvation and excessive exercise, both part of almost all eating disorders, can influence blood’s tryptophan availability.

Food sources of Zinc and Tryptophan

Food sources of tryptophan include:

Milk and cheese

Chicken and turkey

Tuna fish



Dried prunes



 Food sources of zinc include:

Seafood (oysters, crab, lobster)

Red meat and Poultry


Dairy products



Whole grains

Fortified cereals

5 Tips to boost serotonin!

1) Get more sunshine, especially in the first hour after waking up. Go for a walk, get sun in, and spend at least 10 to 15 minutes outside each day.

2) Get a massage; this helps books serotonine and dopamine, another mood-related neurotransmitter.

3) Exercise and move more during the day. No need to run a marathon 30 minutes a day will do the trick.

4) Spend more time with people you love and who love you back. Socializing is essential for mental health. If you live far away from them or for any other reason, you can see them often, then get a dog or a cat. This will also help you boost serotonine.

5) Helps others; volunteering is an excellent activity for your brain researches shown that gratitude can help books serotonin and dopamine.

The bottom line

Nutrition plays a critical role in mental health, and eating disorders are no exception. Those prone to anorexia or bulimia have a particular need for tryptophan and zinc. Deprived of these nutrients, they are more likely to develop unhealthy reactions, including losing or increasing appetite or control. If you are a woman in your fertile years, it is crucial to support your body during the circle to avoid low serotonine, which may trigger binges and low mood.

An excellent place to start is by consuming high Tryptophan and Zinc in foods, but often this is not enough. Discuss supplementation and holistic treatment options with your health provider if you are suffering from an eating disorder.

I hope this article was helpful to you. Do you have further questions, or would you like to share something with me? Please connect with me on social media!


Patrick Holford (optimum nutrition for the mind)