Yogurts are one of the dairy products with the best reputation for the functioning of our immune system. The list of beneficial components is long, being listed in hundreds of advertisements. In addition, yogurts are present in the diets of many cultures in the world, and the production process dates back thousands of years. However, what is the truth in all this praise for yogurt? Is it true that including a yogurt a day in our diet will help us strengthen our immune system?
How is yogurt produced?
The yogurt production process is something that humanity has known and practiced for thousands of years, and it consists of a fermentation process of a dairy product thanks to microorganisms . These microorganisms are specific types of bacteria such as Lactobacillus (or lactobacilli) and Streptococcus . When one type of bacteria comes into contact with milk, they carry out metabolic reactions during which they transform some of the milk’s compounds into yogurt. Today, this process is carried out with a combination of several strains of bacteria and controlled temperature and conditions to generate a yogurt that meets all quality controls.
One of the key points of fermentation includes the transformation of lactose into lactic acid, which gives it the characteristic acid taste due to a drop in the product’s pH. Once the yogurt is formed, the presence of these bacteria is not necessary and can be eliminated by raising the temperature. However, these bacteria are not harmful to our body so it would not be a problem for us if they remain in the yogurt at the time of consumption.
What’s in a yogurt?
When analyzing all the compounds that a yogurt contains without counting the microorganisms, we observe a rich source of proteins, fats and vitamins. In general terms, a normal yogurt can contain a variable range of each of these elements, but calcium is one of the most mentioned among dairy products . Calcium is an essential chemical element in many cells, not only for the maintenance of bones, but also for muscle contraction or even the production of cellular energy . Bone calcium can be stable or dynamic, and when you suffer from a calcium deficit it can have a detrimental effect on the structure and stability of the visible skeleton in the medium and long term. However, there are other places in our body that would be damaged more quickly and severely if we do not take in enough calcium.
And what about our defenses?
The cells of the immune system, of course, also need a flow of calcium to carry out basic processes such as making antibodies or sending signals around the body . Although in a general way, calcium contributes its grain of sand in the correct functioning of the immune system. Yogurt is not the only food that contains calcium, but it can be helpful if you need an increase in calcium in your diet. However, a recent study has shown that calcium levels did not change in people who consumed Greek yogurt in their diet or not, while another did observe a correlation in calcium levels in children and adults who consumed yogurt daily.
Similar effects exist with the other compounds in yogurt and, as a general rule, unless there is a deficiency in any of them, increasing the consumption of this dairy product does not result in a specific boosting of the immune system.
To answer the question if yogurts help strengthen the immune system, it is also important to know if the bacteria are alive or not at the time we consume the yogurt. The microbiota is a determining factor in the correct functioning of the organism , and an imbalance in its variety or quantity can cause acute or chronic diseases. Among those diseases, some are directly related to the immune system. For this reason, if yogurt contains beneficial bacteria for the body and a person has difficulty maintaining the balance of their microbiota, it is possible that the missing bacteria may be provided by this dairy product . However, it is a very delicate situation and should be evaluated by a specialist to determine if adding yogurt to the diet can be a solution. Studies in animal models point to the possible benefit of these bacteria in preventing the development of diseases, but this evidence is difficult to corroborate in humans.
Although the evidence is ambiguous and the effects are limited, yogurts can provide a set of beneficial elements for the body and the immune system by extension. A yogurt a day does not make us immune to infections, but as a dessert, it is not bad at all.
Baranowski et al. 2021. Exploring the Effects of Greek Yogurt Supplementation and Exercise Training on Serum Lithium and Its Relationship With Musculoskeletal Outcomes in Men. Front Nutr. doi: 10.3389/fnut.2021.798036Zhu et al. 2021. Associations between frequency of yogurt consumption and nutrient intake and diet quality in the United Kingdom. J Nutr Sci. doi: 10.1017/jns.2021.63Suzuki et al. 2020. Effect of the Lactococcus Lactis 11/19-B1 Strain on Atopic Dermatitis in a Clinical Test and Mouse Model. Nutrients. doi: 10.3390/nu12030763