Nutriepigenetics, or How We Influence Our Genes with Our Diet
We all know the slogan „you are what you eat.” This statement can be interpreted in many ways. In this article, we will analyze the dietary context in relation to our genome, or more specifically, the epigenome, to find out if and how our genes are influenced by diet.
What is the genome and the epigenome, what do they do?
The human genome can be compared to the motherboard of a computer. It is there that the basic information about the structure and functioning of our body is stored in a chemical form. The information carrier in the genome is a deoxyribonucleic acid (DNA) molecule, while the genetic information is composed of DNA strands in a strictly defined order, consisting of four nitrogen bases (nucleotides). The entire genome contains about 23,000 genes – that is, elements with instructions for building proteins with various functions, including building blocks (e.g. muscles, hair or cells of the immune system) and regulatory (e.g. enzymes, neurotransmitters in the nervous system, hormones).
The epigenome is the part of the genome that modifies the expression of our DNA. This means that it can modify the production of proteins encoded in DNA (accelerate their synthesis or inhibit it). The epigenome can thus act as a kind of on-and-off switch in the synthesis of enzymes, hormones, cells of the immune system, and many others.
DNA epigenetic modifications occur in several ways (through DNA methylation, histone enzymatic modifications and non-coding microRNA3), it is worth noting that they do not change the structure of DNA and do not belong to genetic mutations, but are reversible on and off processes that are changed under the influence of environmental factors . DNA is a relatively stable structure while the epigenome is variable.
How is epigenome related to diet?
One of the epigenetic mechanisms is DNA methylation. The process itself is the attachment or detachment (demethylation) of the so-called methyl group into a DNA molecule. This process works like the on-and-off switch mentioned earlier.
Methylation processes can be influenced by diet. The food ingredient that plays a significant role in this process is folic acid. A diet low in folic acid causes too low DNA methylation, which results in instability during cell division, and this may lead to the development of cancer cells (leukemia, breast, ovarian and prostate cancer) or autoimmune diseases, in particular rheumatoid arthritis, lupus systemic erythematosus, scleroderma, and Sjögren’s syndrome. Apart from folic acid, other sources of methyl groups in the diet are methionine, choline, betaine, and vitamin B12. Other factors that may affect the methylation process are zinc (pumpkin seeds, fish, milk, eggs), selenium (Brazil nuts, fish, poultry) and polyphenols (antioxidants), especially epigallocatechin gallate found in green tea and quercetin (blueberries, blackberries, chokeberry, elderberry, green tea).
Where can we find methyl groups?
We should make sure that our menu includes products rich in folic acid: green vegetables (broccoli, spinach, kale, fresh herbs, green beans, lettuce, Brussels sprouts, green peas, cabbage), cauliflower, beets, legumes, asparagus, citrus fruit.
Methionine, choline and vitamin B12 can be found in meat, eggs, fish, milk, and dairy products. The sources of choline also include wheat germ, legume seeds and nuts.
Factors disturbing the processes of methylation are: deficiencies of methyl groups, zinc, selenium, alcohol consumption, cocaine use, and smoking.
Histone protein acetylation is another epigenetic mechanism that can be influenced through diet. Food ingredients responsible for the modifications are, among others, diallyl sulfide (garlic) and sulforaphane (broccoli, broccoli sprouts). On the other hand, resveratrol (grape) is an activator of sirtuin enzymes. Their activity facilitates fat metabolism, regulates insulin secretion and activates cellular metabolism. Other sirtuin stimulants are caloric deficit and exercise. Resveratrol is characterized by low bioavailability, hence the search for other dietary components that could have a similar effect to resveratrol.
Nutrigenetics is a young field of science that is developing very dynamically. It brings the possibility of improving the adaptation of the diet both to individual needs of the patient in a dietitian’s office and the user of the application which offers a balanced diet. Nutritionists, by following the test results, have the opportunity to include appropriate ingredients in the daily menu of their clients. In our applications, we emphasize that meals contain much more than just the right amount of calories, proteins, fats, and carbohydrates. Research into the influence of diet on epigenetic mechanisms is not easy due to the multitude of environmental factors that affect us constantly. Nevertheless, we try to implement what we know by caring for the health of our clients through a properly composed diet. Our diets contain sources of folic acid, choline, vitamin B12, zinc, selenium, polyphenols, and many other bioactive ingredients. Certainly, in the near future, we will learn about new processes and dependencies as well as potentially beneficial ingredients that will also be included in our diet plans.
Another branch of nutrigenetics is nutrigenetic research, which today allows you to gain knowledge about individual, inborn predispositions to diet-related diseases, intolerance, or metabolic profiles, including learning about our metabolism of proteins, fats, carbohydrates, caffeine, homocysteine, vitamin D, cholesterol , folic acid and others, and examine the antioxidant potential of the body.
It is possible that in the future, a dietitian will ask us to take nutrigenetic tests which will then be the basis for composing an individual diet and proper supplementation. It is also likely that it will become possible to personalize the diet in the application based on these research results. However, we should remember that the potential benefits also carry some risk. There are fears that the knowledge about our genetic predisposition to the development of certain diseases may be used for various purposes, also against us, for example by dishonest employers or insurers. Nutrigenetics is definitely our future and it is up to us how we use the knowledge about our genome.
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