There are studies that show that there are more depressed people in the vegan or vegetarian groups than among the omnivores. However, this does not mean that a vegan or vegetarian diet makes you depressed, but most likely has completely different reasons.
Study: More depression with a vegan diet
In it, researchers from the University of Bristol asked 9,668 male partners of pregnant women about their eating habits and possible depressive symptoms. It turned out that the vegetarian group was more likely to have depressive symptoms than the non-vegetarian group.
Possible other risk factors for depression (age, marital status, employment, housing situation, number of children, religion, depression in the family, smoking, alcohol, etc.) were taken into account in the analysis.
Vegetarians who are not at all
However, some of the men classified as vegetarian were not actually vegetarians, with 7.4 percent reporting that they occasionally ate sausages and burgers, over 10 percent had meat pies and poultry on their “vegetarian” menu, and nearly 60 percent regularly ate fish.
And even if they were vegetarians, the result cannot necessarily be transferred to vegans, since the two forms of nutrition can differ greatly.
However, the British study is not the only one to observe an increased risk of depression among vegans and vegetarians. A meta-analysis by the University of Southern Indiana from 2021 ( 4 ) also showed, based on an evaluation of 20 studies with a total of more than 170,000 participants, that depression and anxiety were less common in the group of meat eaters than in the group of people who give up meat.
Possible reasons why vegetarians are prone to depression
The researchers also write that a reverse connection cannot be ruled out, i.e. that some people first had depression and then changed their diet, e.g. B. because they no longer had an appetite for animal products or had heard that a plant-based diet can help with depression.
However, if this is not the case, then – according to the scientists – the following possible reasons for the increased tendency to depression in vegetarians could be considered:
- A lack of omega-3 fatty acids, since vegans do not eat fish and it is known that the administration of omega-3 fatty acids even has a direct antidepressant effect
- A vitamin B12 deficiency linked to depression
- A lack of vitamin B12 and folate increases homocysteine levels, which promotes depression
- Too much nut consumption – Nuts are high in omega-6 fatty acids, which increase the risk of depression
- Exposure to pesticides may promote depression (fruits and vegetables are high in pesticides, which is why vegans/vegetarians are more exposed to pesticides than omnivores)
- High phytoestrogen blood levels (due to many soy products)
With a plant-based diet, you should of course make sure – as with any diet – that you are well supplied with all vital substances, which should also include targeted dietary supplements with omega-3 fatty acids and vitamin B12 in particular.
Why nuts don’t make you depressed
Because the men labeled vegetarian in the UK study ate nuts more often than non-vegetarians, the study incorrectly concluded that it could be the nuts that caused depression.
Because nuts contain a lot of omega-6 fatty acids (linoleic acid) – and an excess of these fatty acids is considered a risk factor for depression, according to the researchers. A study is cited as proof of this, in which it was actually found that an excess of omega-6 fatty acids could be problematic in this respect.
However, nuts are not mentioned once in this study, so it can be assumed that completely different omega-6 sources are problematic, e.g. B. Fast food, as a list at Nutritiondata shows, whereby hardly any of the foods listed here are vegetarian, let alone vegan.
Pesticide exposure in vegan and vegetarian diets
The British study explains that exposure to pesticides increases the risk of depression and that vegetarians are more exposed to pesticides because they eat more fruit and vegetables – and fruit and vegetables, in particular, are contaminated with pesticides.
This statement is backed up by a 2017 study that only screened 42 people from a particular settlement in Israel. However, these results are not generally transferrable to vegetarians or vegans. So it could e.g. could be, for example, that pesticides were used more intensively at this very location in Israel.
With high antioxidant consumption, pesticides are better tolerated
It should also be considered that exposure to pesticides alone does not allow any statement to be made about the effects of this exposure. So could e.g. It may be the case, for example, that with the increased consumption of conventionally produced fruit and vegetables, you consume more pesticides, but these do not have a harmful effect because you are also very well supplied with vital substances and antioxidants (which in turn can prevent harmful effects/oxidative neutralize stress) and has healthy elimination organs (intestines, liver, kidneys), which contribute to the good elimination of toxins.
Vegans are less exposed to pollutants
A French study in 2017 also found that vegans are even less exposed to chlorinated hydrocarbons, less to the so-called persistent (long-lived, i.e. difficult to degrade) organic pollutants, and also less to some mold toxins than the rest of the population. They are more likely to be exposed to higher loads, e.g. B. exposed to cadmium and aluminum.
A vegan diet protects against damage caused by harmful substances
As early as 2006, however, Slovakian researchers explained that although vegans and vegetarians are more exposed to cadmium, which could theoretically contribute to increased oxidative stress and thus to liver and kidney damage, plant-based eaters, in particular, have higher levels of antioxidants, which in turn are more vulnerable to cadmium-related damage protect.
As far as aluminum is concerned, the Federal Institute for Risk Assessment does not indicate a higher exposure in vegetarians than in omnivores.
High levels of phytoestrogens in vegan diets
The British study also cited the high phytoestrogen content of vegan or vegetarian diets as a possible reason for the increased risk of depression in the vegan and vegetarian groups of people. Soy products in particular contain phytoestrogens in the form of isoflavones.
In the vast majority of studies on this topic, however, the opposite is discussed, namely whether soy isoflavones should not be used therapeutically against depression, whereby the required dose – according to a study from 2016 – could also simply be taken from a diet containing soy.
Creatine deficiency as a risk factor for depression?
Recently, vegans and vegetarians are more often recommended to take creatine. Because creatine is a substance that is found almost exclusively in meat, sausage, and fish and to a lesser extent in dairy products, but hardly at all in plant foods. Could Creatine Deficiency Lead to Depression in Vegans?
A 2020 study states that in the group of low creatine eaters, 10 per 100 people suffer from depression. In the high creatine eaters, it was only about 6 per 100. From this, one could conclude that creatine deficiency could be one of the reasons for depression.
Correlation yes, causation no
Basically, however, this study is just another indication that depression occurs somewhat more frequently in the group of people who eat little creatine and therefore little meat. However, it does not automatically mean that low creatine or low meat are also the cause of this depression.
Creatine is produced by the body itself
Because creatine can also be produced by the organism itself – not only in the liver and kidneys but also in the brain. A study from 2014 specifically examined the creatine supply of the brain in vegetarians compared to normal eaters.
Here, too, it was logical that the vegetarians consumed significantly less creatine in their food than omnivores. Nonetheless, brain creatine levels were similar in both, in fact, slightly higher in the vegetarians. The brain is therefore self-sufficient in terms of creatine supply and not dependent on the creatine intake from food. However, it makes its own creatine (17) from the three amino acids arginine, glycine, and methionine.
Therefore, just make sure you have an adequate protein supply so that your body can also produce enough creatine from the corresponding amino acids (arginine, glycine, and methionine).
Since vegans and vegetarians have different values and are also more socially oriented – this is the second reason that the two psychologists name – it obviously weighs them down much more than an omnivore when they experience injustice and violence against others (whether human or animal) on a daily basis ) experience.
Also, vegan eaters tend to be more concerned about the environment, global warming, devastated rainforests, endangered species, raging wars in many regions of the world, etc.
Studies have shown that the more social a person is, the greater the risk that their psychological well-being will suffer. e.g. For example, those who perceive injustices or the threat to the environment very strongly do not feel so good mentally.
Of course, omnivores are not insensitive to the problems mentioned, but studies clearly show that vegans and vegetarians are more sensitive than omnivores, so their well-being suffers more than that of non-vegetarians.