Nutri Courses

Advisory

Citrus fruits

Citrus fruits are a group of fruits that include oranges, lemons, grapefruits, limes, and tangerines. They are generally known for their high vitamin C content. Citrus fruits are also a significant source of fiber, which can help regulate blood sugar levels and support digestive system health. The fruit contains a high proportion of water, and their consumption thus helps to maintain hydration.

Hello,
I would like to ask, regarding fruit, you mentioned that an increased amount of citrus can cause mucus formation. In traditional remedies, water with lemon is used to reduce mucus, so in the short term, could it help after all? I would appreciate a brief explanation of the process by which milk causes mucus formation (dairy products are commonly recommended to be avoided during illnesses due to mucus formation).

This issue needs to be approached holistically, meaning that the effect of food on mucus production should not be generalized in the sense of "I eat a particular food and the result is excessive mucus production."

Firstly, it is important to distinguish which part of the organism we are talking about when addressing the impact of food on mucus production. Some substances in foods directly increase mucus production in the respiratory tract mucosa, others in the digestive system, and still others in the excretory system.

It is also necessary to consider the health situation - in a healthy individual, the extent of the effect will be significantly smaller than in cases of health/metabolic disorders.

Furthermore, environmental temperature and the quantity of food consumed also play a role. A typical example is water with lemon/lime, where organic acids from the citrus temporarily increase the activity of mucus-producing cells after consumption. Given that the amount of lemon/lime juice is very small compared to consuming the whole fruit, the response of the cells in terms of overall mucus production is correspondingly small. This means a smaller reaction results in lower production, which facilitates easier expectoration while the lower pH of the fluid helps dissolve the mucus.

Milk/dairy products work somewhat differently - in healthy individuals, they do not affect respiratory tract mucus production. However, in cases of lactose intolerance, they can indirectly support the formation of mucus in the intestinal mucosa and worsen the existing mucus condition in upper respiratory tract inflammations.

Hello, I would like to ask about citrus fruits and fruits that do not grow in our region. Is it a mistake to include them in the daily diet, especially during winter, or would it be more appropriate to stick to local fruits? What about fruits that we have frozen in the freezer, like raspberries and strawberries, and use them in the winter—does this contradict the theory of cooling and warming the body, or is it enough to cook them after thawing? Thank you.

It's certainly not a mistake, but it's important to realize that such effort carries certain "risks." From a thermal perspective, most types of exotic fruits are typically refreshing to cooling, and sensitive individuals will always react to this. Additionally, there's the freshness factor, as the fruits are harvested unripe and travel halfway across the world. The process of ripening during transport and storage, with few exceptions (e.g., bananas), is not nutritionally complete. To this, you can add the risk of the presence of molds or chemicals used to treat the surface of the food. A rational perspective on the situation should lead to the decision to focus on local production, which is not only nutritionally more advantageous but also essentially more natural. Freezing the fruit does not affect its thermal nature; this characteristic remains the same.

Questions answered by

Mgr. Martin Jelinek
Lecturer and author of the educational system

Mgr. Martin Jelínek has been systematically involved in nutrition education since 1999. He is the founder of ATAC, the educational company behind NutriCourses, and the author of an educational system focused on nutrition, healthy lifestyle, and the practical application of nutrition knowledge.

He graduated from the Faculty of Science at Masaryk University in Brno. Throughout his professional career, he has combined nutrition, education, and the practical application of acquired knowledge. His educational system also includes the ZOF (Zone of Optimal Functioning) learning application, where students turn theory into practical work with meal plans.

In 2007, he launched the first intake of a six-month course focused on the education of nutrition advisors. Over time, this course became the foundation for the further development of the educational system and a range of specialised courses.