In recent years, “personalized nutrition” that utilizes individual genetic information has been attracting attention. Because the rate at which nutrients are absorbed and metabolized differs depending on genetic differences, optimal nutritional intake based on individual genetic characteristics is required, rather than uniform dietary advice. In this article, we will provide a detailed explanation of the relationship between genetic information and nutrition based on the latest research.
1. Relationship between gene polymorphisms and nutrition
What is genetic polymorphism?
Genetic polymorphism refers to the phenomenon in which a specific base sequence in DNA differs from person to person. It is known that this difference affects the absorption, metabolism, and excretion of nutrients. For example, a mutation in a certain gene may increase or decrease the requirement for a vitamin or mineral.
The MTHFR gene and folate metabolism
Polymorphisms in the MTHFR (methylenetetrahydrofolate reductase) gene (especially the C677T mutation) are involved in the metabolism of folic acid, and people with this mutation are unable to efficiently produce the active form of folic acid (5-methyltetrahydrofolate), which may increase the risk of neural tube defects and cardiovascular disease. It has been reported that adequate intake of folic acid can reduce these risks.
The LCT gene and lactose intolerance
The LCT gene determines the activity of lactase (an enzyme that breaks down lactose). If there is a mutation in this gene, lactase activity decreases in adults, and people may develop “lactose intolerance,” which causes indigestion and stomach pain when drinking milk. Choosing low-lactose foods such as yogurt and cheese when consuming dairy products can help reduce symptoms.
2. Epigenetics and Nutrition
What is epigenetics?
Epigenetics is the phenomenon in which gene expression can change without altering the DNA sequence. Dietary and environmental influences can regulate gene expression through mechanisms such as DNA methylation and histone modifications.
The impact of nutrients on epigenetics
Folic acid and B vitamins : Involved in DNA methylation and may be useful in preventing cancer risk and metabolic diseases.
Polyphenols (green tea catechins, resveratrol) : These have antioxidant properties and are thought to suppress inflammation and aging through epigenetic changes.
Omega-3 fatty acids : They are said to suppress inflammation and contribute to improved brain function, and may affect the development of the fetus’s brain, especially when consumed by the mother during pregnancy.
3. Nutritional management using genetic information
The Importance of a Personalized Diet
Genetic testing can be used to create a personalized diet plan. For example, people with a mutation in the obesity-related gene (FTO gene) are more susceptible to the effects of a high-fat diet and may benefit more from a lipid-restricted diet than a carbohydrate-restricted one.
The relationship between exercise and genes
The relationship between nutrition and exercise is also influenced by genes. The ACTN3 gene is involved in the development of fast-twitch muscles, and mutations in this gene affect how easily muscles develop, which results in individual differences in the effects of strength training.
Mutations in the TCF7L2 gene are known to increase the risk of developing type 2 diabetes. People with this gene mutation are less efficient at metabolizing carbohydrates, so blood sugar control is important. A diet centered on low glycemic index foods is recommended.
Cardiovascular disease and the APOE gene
People with the E4 type of APOE gene have a different cholesterol metabolism than normal and tend to be at higher risk of arteriosclerosis. In this case, it is recommended to limit saturated fatty acids and increase the intake of omega-3 fatty acids and dietary fiber.
5. Use of genetic testing and future prospects
Benefits of Genetic Testing
Choose the diet and exercise that’s right for you
Helps prevent lifestyle-related diseases
Effective diet and performance improvement possible
Points to note when using genetic information
Genetic information only indicates “risk” and “tendency,” and lifestyle habits also have a large influence.
It is important to choose a genetic test that is scientifically based
Use it in consultation with a doctor or specialist.
6. Relationship between genes and mineral metabolism
Iron metabolism and the HFE gene
Iron is a component of hemoglobin in blood and is an essential mineral for transporting oxygen. However, if there is a mutation in the HFE gene, the body is more likely to absorb excessive iron. Since people with this gene mutation are prone to developing hemochromatosis (iron overload), it is important to moderately limit their intake of red meat and foods high in iron. Conversely, people with a genotype that is at high risk of iron deficiency anemia are recommended to actively consume iron-rich foods such as liver and spinach, and take them together with vitamin C to increase absorption.
Calcium metabolism and the VDR gene
The VDR (vitamin D receptor) gene plays an important role in regulating calcium absorption. Mutations in this gene lead to reduced calcium absorption efficiency and a tendency to have low bone density. In particular, postmenopausal women are at increased risk of osteoporosis, so adequate calcium and vitamin D intake is important. In addition to dietary intake, it is also recommended to generate vitamin D through moderate exposure to sunlight.
7. The relationship between genes and antioxidant activity
SOD2 gene and oxidative stress resistance
The SOD2 (superoxide dismutase) gene supports the function of antioxidant enzymes that remove active oxygen. Mutations in the SOD2 gene may reduce resistance to oxidative stress and increase the risk of cell aging and inflammatory diseases. People with this genotype can protect their bodies from oxidative stress by consciously consuming foods rich in polyphenols and vitamins C and E (blueberries, nuts, green tea, etc.).
Relationship between the GPX1 gene and selenium
The GPX1 gene is involved in the function of the antioxidant enzyme glutathione peroxidase. This enzyme utilizes the mineral selenium to protect cells from oxidative stress. People with certain polymorphisms in the GPX1 gene may have increased selenium requirements, and are advised to actively consume selenium-rich foods such as Brazil nuts and seafood.
8. Lifestyle optimization using genetic information
Customize your meals
Based on the results of your genetic test, you can choose a diet that suits your constitution. For example, people with a genetic type that has a slow lipid metabolism will benefit from a diet centered on blue fish, which is rich in omega-3 fatty acids. On the other hand, people with a genetic type that has an inefficient carbohydrate metabolism should aim for a diet centered on low GI foods to avoid a sudden rise in blood sugar levels.
Optimize your exercise routine
Your genes also affect what type of exercise works best for you. For example, people with certain mutations in the ACTN3 gene are better suited to endurance exercise (marathons and cycling) than to explosive exercise. Understanding your genetic characteristics can help you continue exercising effectively and comfortably.
Proper Use of Supplements
If you have a genetic need for a certain nutrient, it may be difficult to get enough of it through diet alone. In such cases, it is possible to supplement your nutritional balance by using supplements. However, excessive intake can pose health risks, so it is important to consult with a specialist and take the appropriate amount.
9. The future of genetic testing and future possibilities
Utilizing AI and big data
The use of AI that combines genetic information and nutritional data is becoming more common. This has resulted in the emergence of services that can instantly create nutritional plans optimized for individuals and provide meal suggestions. In the future, it will be possible to receive real-time nutritional advice based on genetic information through smartphone apps.
Integration with precision medicine
Personalized nutrition using genetic information may be integrated with precision medicine and used as part of disease prevention and treatment. It is believed that nutritional intervention at the genetic level will become particularly important in cancer treatment and the prevention of lifestyle-related diseases.
Genetic ethics and privacy protection
The use of genetic information also entails ethical issues. Genetic information is highly sensitive personal information, and inappropriate handling of it can lead to violations of privacy. Therefore, when undergoing genetic testing, it is important to choose a trustworthy institution and carefully consider how the data will be handled.
10. The relationship between genes and mental health
Serotonin transporter (5-HTTLPR) and mood stability
Serotonin is a neurotransmitter involved in mood stability and happiness, and it is known that polymorphisms in the serotonin transporter gene (5-HTTLPR), which is responsible for transporting serotonin, affect mental state. People with the “short type (S type)” of this gene may be more susceptible to stress and have a higher risk of anxiety and depression. On the other hand, people with the “long type (L type)” tend to have relatively high stress resistance.
For people with the S gene, consuming foods containing tryptophan and omega-3 fatty acids (DHA and EPA) (oil-filled fish, nuts, bananas) can promote the production of serotonin and help stabilize mood. It is also said that incorporating mindfulness and moderate exercise (yoga and walking) can help manage stress.
BDNF gene and brain plasticity
Brain-derived neurotrophic factor (BDNF) is a protein involved in brain plasticity (learning and memory formation), and it is known that a polymorphism (Val66Met mutation) in the BDNF gene that controls its production affects cognitive function and resistance to mental stress. People with the Met type gene tend to have poor memory and are vulnerable to stress, so it is recommended that they be conscious of their diet and lifestyle habits that increase BDNF.
To increase BDNF, it is important to consume foods with high antioxidant properties (blueberries, walnuts, green tea) and high protein foods (eggs, fish, soybeans). In addition, aerobic exercise (running, cycling) and good quality sleep also promote the secretion of BDNF and maintain brain health.
11. The relationship between genes and intestinal environment
Interactions between gut bacteria and genes
Recent research has revealed that the interaction between the intestinal flora (microbiome) and genes has a significant impact on health. Different genes affect the composition of intestinal bacteria, which can affect nutrient absorption and immune function.
For example, the ability of gut bacteria to produce short-chain fatty acids (acetic acid, butyric acid, and propionic acid) is determined by certain genes. Short-chain fatty acids maintain intestinal health and suppress inflammation. To promote their production, it is important to actively consume fermented foods (yogurt, kimchi, natto) and foods high in dietary fiber (vegetables, whole grains, and beans).
The FUT2 gene and probiotics
The FUT2 (fucosyltransferase 2) gene is involved in the growth of intestinal bacteria, and it has been suggested that people with certain polymorphisms in this gene are more susceptible to the effects of probiotics (lactic acid bacteria and bifidobacteria). People with this type of gene may be able to improve their intestinal environment more effectively by consciously consuming yogurt and fermented foods.
12. Genetic anti-aging strategies
Telomere length and aging
Telomeres are structures that protect the ends of chromosomes, and as their length shortens, cellular aging progresses. In order to maintain telomere length, not only genetic factors but also lifestyle habits and nutritional intake play an important role.
In particular, the following nutrients are effective in protecting telomeres:
Resveratrol (red wine, grapes, dark chocolate) : Antioxidant that may reduce telomere shortening.
Omega-3 fatty acids (oil, flaxseed oil) : They are said to suppress cellular inflammation and slow down aging.
Vitamin D (fish, eggs, sunbathing) : It is involved in cell repair and is expected to have the effect of boosting immune function.
The FOXO3 gene and longevity
The FOXO3 gene is one of the important genes related to longevity, and people with certain mutations in this gene tend to have a lower risk of age-related diseases. Calorie restriction (avoiding excessive energy intake), consumption of foods rich in polyphenols, and moderate exercise are effective in increasing FOXO3 activity.
13. Advances in genetic analysis and the future of personalized medicine
CRISPR technology and the potential of gene editing
Advances in CRISPR-Cas9 technology may one day make it possible to edit specific genes to reduce disease risk or improve nutrient metabolism, but this technology comes with ethical issues and requires careful discussion.
Integration of wearable devices and genetic information
In recent years, health management that combines genetic information with wearable devices (smart watches and health monitors) has been attracting attention. By integrating genetic data with real-time health data (heart rate, blood sugar level, sleep patterns, etc.), more precise nutritional advice can be provided.
14. The relationship between genes and detoxification
The relationship between detoxification enzymes and genes
Our bodies use detoxification enzymes to break down and excrete harmful substances such as food additives, environmental pollutants, alcohol, drugs, etc. Detoxification ability varies from person to person depending on the genetic polymorphisms that produce these enzymes.
Some of the most common detoxifying enzymes are:
CYP1A2 gene : Responsible for the metabolism of caffeine and carcinogens (heterocyclic amines). People with low CYP1A2 activity metabolize caffeine slowly, increasing the risk of insomnia and palpitations due to excessive intake.
GST (glutathione S-transferase) gene : Detoxifies harmful substances. Deletion of the GSTM1 gene may reduce the body’s ability to detoxify, making the body more susceptible to environmental pollutants.
To enhance your body’s detoxification function, foods that contain the following nutrients are effective:
Sulforaphane (broccoli, cabbage, kale) : Promotes GST activity, making it easier to excrete harmful substances from the body.
Curcumin (Turmeric) : Has anti-inflammatory properties and supports liver detoxification.
15. The relationship between genes and food allergies
HLA genes and allergic reactions
Food allergies occur when the immune system overreacts to certain food components. Certain polymorphisms in the HLA (human leukocyte antigen) genes are involved in the risk of developing various allergies, such as gluten intolerance (celiac disease) and peanut allergy.
The most common food allergies linked to HLA genes include:
HLA-DQ2/DQ8 gene : Strongly associated with celiac disease (hypersensitivity to gluten). People with this gene are more likely to develop intestinal inflammation when they consume wheat products.
HLA-DRB1 gene : May increase the risk of developing allergies to nuts and shellfish such as shrimp and crab.HLA-DRB1 gene : May increase the risk of developing allergies to nuts and shellfish such as shrimp and crab.
For people with food allergies, it is important to maintain a balanced diet while making good use of alternative foods. For example, people with gluten intolerance can avoid wheat products and still get the nutrients they need by using quinoa, buckwheat, or almond flour.
16. Relationship between genes and the body clock (circadian rhythm)
PER3 gene and sleep patterns
The body’s internal clock (circadian rhythm) controls physiological functions such as sleep, hormone secretion, and metabolism, and varies from person to person depending on genes. It has been shown that polymorphisms in the PER3 gene affect sleep length and morning/evening tendencies.
People with the long PER3 variant : tend to be early risers and have a low tolerance for sleep deprivation.
People with short PER3 variants : They tend to be nocturnal and can function relatively well even with short amounts of sleep.
To improve the quality of your sleep, it is important to create a lifestyle that suits your constitution. Morning people can easily reset their biological clock by being exposed to morning light. On the other hand, night owls can benefit from avoiding blue light before bed and creating a relaxing environment.
17. Ethical issues and social impacts of genetic analysis
Privacy protection and data security
Genetic information is highly personal data and requires careful consideration when handling it. In recent years, the number of companies offering genetic testing has increased, but it is important to check the security of data and their policies regarding the provision of data to third parties.
When using genetic information, the following points must be considered:
Get tested by a trusted institution : Choose companies and medical institutions that provide scientifically reliable data.
Confirm the extent of data sharing : Understand the risks of genetic information being shared with third parties and ensure that privacy protection measures are in place.
Avoid excessive self-diagnosis : Genetic information only indicates trends, so it is important to use it in consultation with a doctor or specialist.
Social use of genetic information
In the future, genetic information may be widely used not only in medicine, but also in the fields of sports science, beauty, and mental health. For example, we will likely see an increase in services tailored to individual characteristics, such as genetically-based skin care products and individualized programs to increase stress resistance.
At the same time, laws and regulations are also needed to prevent genomic discrimination based on genetic information. Fair rules must be established to prevent restrictions on employment or insurance enrollment based on genetic information.
18. Genetic information and sports performance optimization
ACTN3 gene and muscle type
Genes play an important role in sports performance. In particular, the ACTN3 gene is involved in the development of fast-twitch muscle fibers and is considered one of the factors that determine muscle characteristics.
RR type (has two functional genes) : Good development of fast-twitch muscles, suitable for power sports such as sprinting and weightlifting.
RX type (has one functional gene) : A balanced type that is easily adapted to both endurance and power training.
XX type (no functional gene) : Predominantly slow-twitch muscles (slow twitch), suitable for endurance sports such as marathons and cycling.
By understanding your ACTN3 type, you can create a more efficient training plan. For example, if you are an RR type, it is more effective to focus on high-intensity training to improve your explosive power, while if you are an XX type, it is more effective to focus on long-term aerobic exercise.
The PPARGC1A gene and endurance
The PPARGC1A gene is involved in mitochondrial production and energy metabolism, and affects the improvement of endurance. People with certain variants of this gene are said to have high oxygen consumption efficiency and are suitable for long-distance runners and triathletes. To improve endurance, training that combines HIIT (high-intensity interval training) and aerobic exercise is recommended.
Personalized sports nutrition
Optimizing sports nutrition based on genetic information is also attracting attention. For example, people with genes that slow recovery can speed up recovery by consuming more anti-inflammatory foods (turmeric, ginger, omega-3 fatty acids). Also, people who have slow muscle synthesis should be conscious of high-protein meals and properly manage the timing of nutritional supplementation after training.
Genetic information only indicates “tendencies” and does not determine absolute destiny. Since the environment and lifestyle have a significant impact on gene expression, it is important to manage your health from a comprehensive perspective, rather than adopting extreme dietary restrictions or training methods simply based on your genotype.
How to use genetic test results
Consult with an expert : Correctly understand the results of your genetic test and use them under the guidance of a nutritionist or doctor.
Compare it to your actual physical condition and lifestyle : Try and adjust the nutrition and exercise methods that are tailored to your genotype to see if they actually work for you.
Think about health from a long-term perspective : Genetic information is not a passing trend, but information that should be used to help manage your health throughout your life
Summary
By utilizing genetic information, it may be possible to practice optimal nutrition, exercise, and lifestyle for each individual. It is known that certain gene polymorphisms affect nutrient metabolism, endurance, mental health, detoxification ability, and more. However, genes only indicate “tendencies,” and environmental factors and lifestyle habits are also important. Making good use of genetic information while incorporating a balanced diet, appropriate exercise, and healthy habits will lead to optimal health management.
