In the case of suffering stress, it is usually recommended to do more sport or practice some method of relaxation. While this is really effective, dietary changes can also prove very helpful. One study showed that a certain diet, the so-called Psychobiotic diet, can reduce anxiety and stress.
- Influence of diet on mental health
- Relationship between gut microbiota and stress
- What is the psychobiotic diet?
- What is the portion size?
- Psychobiotic nutrition against stress
There are probiotics and prebiotics, but there are also the lesser-known Psychobiotic. Psychobiotic are foods that have a beneficial effect on the psyche through their influence on the intestinal flora.
A study by APC Microbiome Ireland, a group of scientists from Ireland dedicated to investigating the gut microbiome, has shown that psychobiotic nutrition can increase resistance to stress. The study has been published in the journal Molecular Psychiatry.
INFLUENCE OF DIET ON MENTAL HEALTH
One of the authors of the study, John Cryan, has written in The Conversation, that “over the past ten years, numerous studies have shown how great the influence of nutrition can be on our mental health; In fact, the impact is so great that a healthy diet can reduce the risk of many common mental illnesses.”
The full details of how diet affects the psyche are not yet known. One possible explanation is the connection between the brain and gut flora. The brain and intestines can constantly communicate with each other through the so-called gut-brain axis, composed of the central nervous system, the neuroendocrine and neuroimmune system, the hypothalamic-pituitary-adrenal axis, the sympathetic and parasympathetic arms of the autonomic nervous system, the enteric nervous system, the vagus nerve and the intestinal microbiota.
The areas of the brain in which emotions arise or are responsible for our cognitive abilities are also in close contact with the digestive system through the gut-brain axis.
RELATIONSHIP BETWEEN GUT MICROBIOTA AND STRESS
Previous studies have shown that stress and certain behaviors are related to the state of the gut microbiota. However, it wasn’t clear whether a change in diet could actually affect stress levels.
And this is where the work of John Cryan and his team begins. The researchers invited 45 healthy people to participate in their study. They observed that the participants, who ranged in age from 18 to 59, had previously followed a fairly low-fiber diet.
Participants were divided into two groups. One received a “psychobiotic diet” developed by nutritionist Kirsten Berding, which included foods that can lead to better mental health, specifically prebiotics and fermented. The study lasted four weeks.
WHAT IS THE PSYCHOBIOTIC DIET?
Dr. Berding’s psychobiotic diet includes daily:
- 6 to 8 servings of fruits and vegetables rich in prebiotic fiber, including onions, leeks, cabbage, apples or bananas.
- 5 to 8 servings of whole grains.
- 2 to 3 servings daily of fermented foods, such as sauerkraut, kefir, kombucha, or kimchi.
- 3 to 4 servings of legumes a week.
The other group of participants only received general nutrition advice and were urged to follow the usual guidelines of a healthy omnivorous diet. If you want to adapt this model to the ovo-lacto-vegetarian diet, you will have to increase the portions of legumes, until you reach 1-2 daily (including soy and its derivatives).
WHAT IS THE PORTION SIZE?
Portion sizes usually vary from country to country. In the Irish study, the following ration sizes were used:
- 1 serving of whole grain cereal is, for example, 1 slice of wholemeal bread, 1/200 cup of unsweetened muesli or <> cup of <> ml of brown rice or cooked wholemeal pasta.
- 1 serving of fruit and vegetables is for example 1 apple, 10 grapes, 5 strawberries, two tangerines, a bowl of lettuce, 1/2 cup cooked vegetables
- 1 serving of fermented feed is 200 ml for a liquid food or 1 cup of 200 g for sauerkraut or similar.
- 1 serving of legumes is 200/<> cup of <> ml, in cooked form.
PSYCHOBIOTIC NUTRITION AGAINST STRESS
At the end of the study (after 4 weeks), consumers of the psychobiotic diet reported less stress than participants in the other group. The more consistently they followed psychobiotic nutrition guidelines, the less stress they experienced.
Sleep quality improved in both groups, but the benefit was greatest in the psychobiotic eating group. This is not surprising, as previous studies have shown that the gut microbiota is also involved in the sleep process.
The composition of the gut microbiota was slightly modified as a result of the psychobiotic diet. However, levels of certain substances (short-chain fatty acids and tryptophan) produced by gut bacteria increased significantly, and these substances, in turn, are closely linked to mental health, which could also explain why psychobiotic users felt less stress and slept better.
Scientific references:
- Kirsten Bersing et al. Feed your microbes to deal with stress: a psychobiotic diet impacts stability and perceived stress in a health adult population. Molecular Psychiatry.
- Marx, W et al. Diet and depression: future needs to unlock the potential. Mol Psychiatry.
- Jacka, FN et al. A randomized controlled trial of dietary improvement for adults with major depression (the ́SMILES ́trial). BMC Med.
- Foster JA et al. Stress & the gut-brain axis: Regulation by the microbiome. Neurobiol Stress. 2017.
- Sen P et al. Microbiota and sleep: awakening the gut feeling. Trends Mol.
- Spichack S et al. Mining microbes for mental health: Determining the role of microbial metabolic pathways in human brain
