There are various hormones like Leptin, Ghrelin, and Neuropeptides that regulate hunger and satiety (feeling full) responses. The genes associated with the secretion of these hormones also influence factors like excessive snacking, emotional eating, preference for high caloric food, and persistent hunger. People with certain genetic types may have an increased secretion of Ghrelin (appetite inducer) and lesser secretion of Leptin (appetite suppressor) hormones. Such people tend to overeat as they may not experience the normal feeling of "fullness." Overeating impacts our health in a bad way by increasing the risk of obesity, diabetes, mental issues, and acid reflux issues.
Vitamin A is required for clear vision, healthy skin, and enhanced immunity. Animal sources provide vitamin A in the form of retinol (an active vitamin A derivative), while some plant sources provide vitamin A in the form of carotenes, which must be converted to retinol. This conversion is extremely variable in up to 45% of healthy individuals. Changes in the BCMO1 gene leads to a large difference in the amount of vitamin A produced. People with certain genetic types need more vitamin A in their diet to compensate for less efficient conversion of carotenoids to retinol, especially vegetariansand vegans.
Phosphate works along with calcium to form the bones and teeth. It is also used as a building block for several important molecules, including the DNA. Your body tends to absorb less phosphate when your calcium levels are too high. Like calcium, phosphate also needs vitamin D for absorption. Both higher and lower levels of phosphate in the body can weaken the bones. Some genes affect the body's ability to store phosphorus by excreting too much of it and absorbing too little of it. People with such genetic types need more phosphate in their diet to meet their daily requirements.
Zinc is an essential and trace mineral that is crucial for the proper functioning of the immune system, cell division, cell growth, and the breakdown of carbohydrates. Since the human body does not store excess zinc, it must be consumed regularly as part of the diet. A deficiency in zinc intake/uptake can make a person more susceptible to disease and illness. Zinc deficiency is characterized by hair loss, lack of alertness, and a reduced sense of taste and smell. People with certain genetic types may be at risk for zinc deficiency and may benefit from zinc supplementation.
Vitamin B2 (riboflavin) is essential for human health. It acts as an antioxidant within the body, playing a vital role in skin protection. The body can store only a small amount of vitamin B2, and thus, it needs to be consumed every day. Vitamin B2 deficiency damages the skin by causing cracked skin, itching, and dermatitis. It also leads to elevated levels of homocysteine (a harmful amino acid) in the body. This risk for vitamin B2 deficiency increases with age, illness, and alcohol consumption. People of certain genetic types may need more vitamin B2 due to the inefficient transport in their bodies.
Vitamin B6 (pyridoxine) is required for the proper utilization of sugars, fats, and proteins in the body. It is responsible for forming heme (an iron-containing compound which is a part of the hemoglobin molecule). When the body does not get the required amount of vitamin B6, it leads to a deficiency of the vitamin. Dietary vitamin B6 deficiency is rare as many foods we eat regularly contain adequate amounts of vitamin B6. However, people with certain genetic types cannot fully metabolize this vitamin, leading to its low levels in the body. Such individuals may need more vitamin B6 in their diet.
Vitamin B9, also known as folate, plays a major role in the formation and repair of DNA. It is also essential for the conversion of amino acid homocysteine (the build-up of which is harmful) to another amino acid, methionine. Excess accumulation of homocysteine can be harmful. The folic acid form of vitamin B9 is better absorbed by the body. Folate deficiency is usually a result of poor diet, alcoholism, certain medications, and malabsorptive disorders. People with certain genetic types need more vitamin B9 in their diet due to insufficient absorption of the natural form of folate by the body.
Vitamin B12 (cobalamin) is actively involved in red blood cell maturity. It also helps in the removal of homocysteine from the cells. Vitamin B12 can be obtained from eggs, poultry, meat, fish, etc. The normal level of vitamin B12 in blood is around 200-900 pg/mL. Levels lower than this may indicate a vitamin B12 deficiency, which can lead to anemia and general fatigue. The FucosylTransferase 2 (FUT2) gene is associated with the absorption of vitamin B12 in the gut. People with certain types of the FUT2 gene need more Vitamin B12 in their diet due to lesser absorption in the body.
Vitamin C, also known as ascorbic acid, is a water-soluble essential vitamin. It is a potent antioxidant that supports normal growth and development. Vitamin C is also crucial for a good immune system. Most mammals synthesize vitamin C on their own; however, humans cannot produce this vitamin and depend on dietary sources. Most people can meet their vitamin C requirements through food sources like oranges, strawberries, and broccoli. However, people with certain genetic types need more vitamin C in their diet due to inefficient absorption from food sources. These individuals may require additional vitamin C supplementation.
Vitamin D, also known as calciferol, is necessary for strong and healthy bones. Calcium, a crucial component of bones, can be absorbed only when there are adequate vitamin D levels in the body. Our body makes vitamin D naturally on exposure to sunlight. You can also get vitamin D through dietary sources and supplements. Up to 42% of the adult population in the United States has low vitamin D levels, which can cause health problems. People with certain genetic types need more vitamin D in their diet or vitamin D supplements due to inefficient absorption by the body.
Vitamin E is a fat-soluble vitamin and a potent antioxidant. It helps protect your cells from damage and enhances immune function. Most people get enough vitamin E from the foods they eat. Some vitamin E-rich foods include vegetable oils, cereals, meat, poultry, eggs, fruits, and vegetables. The vitamin E levels in the body depend on the liver, which takes up the nutrient after the various forms of it are absorbed in the small intestine. People with certain genetic types need more vitamin E in their diet due to inefficient transport to or absorption by the liver resulting in lower plasma levels.
Vitamin K refers to a group of fat-soluble vitamins that play a role in blood clotting. It also helps your body make proteins for healthy bones and tissues. Vitamin K is produced in our bodies by the good bacteria in the intestines. The two natural forms of vitamin K are vitamin K1 and vitamin K2. Vitamin K is found throughout the body, including the liver, brain, heart, pancreas, and bone. While vitamin K deficiencies are rare in adults, people with certain genetic types may have inefficiency in producing and absorbing vitamin K and may need additional supplementation.
Calcium is essential for maintaining the strength and structure of bones and teeth. It plays a vital role in certain metabolic functions. An adequate level of calcium in the body over a lifetime can help prevent osteoporosis. Calcium levels are tightly regulated by two main hormonal systems, i.e., parathyroid and vitamin D, which themselves are influenced by genetic factors. Any changes in these genetic factors can lead to higher or lower than normal calcium levels in the body, both of which are dangerous. People with these genetic types may either need to increase or decrease calcium consumption.
Choline is a water-soluble compound that is neither a vitamin nor a mineral. It is an essential nutrient that plays an important role in liver function, nerve function, normal brain development, muscle movement, and supporting a healthy metabolism. Requirements of choline are largely affected by factors like gender, age, physical activity, availability of other nutrients (for example folate, vitamin B6), and genetics. People with certain genetic types may require more choline in their diets due to an inefficiency in choline uptake/metabolism. These people are likely to experience adverse health consequences when on a low choline diet.
Copper is an essential trace mineral necessary for survival. It aids the absorption of iron and enables the body to form red blood cells or the RBCs. Copper is also vital for heart health, immune function, neuron signaling, and collagen production. Copper imbalances have been linked to diseases like Alzheimer's, Wilson's, and Menkes. Some dietary sources of copper include shellfish, seeds and nuts, organ meats, wheat-bran cereals, whole-grain products, and chocolate. Copper is also available as dietary supplements. People with certain genetic types may require more copper in their diets due to an inefficiency in copper uptake/metabolism.
Iron is essential for the production of a protein, hemoglobin. This protein is required to transport oxygen in the blood. About 70% of the body's iron is found in hemoglobin and some in muscle cells in the form of myoglobin. Iron is also essential for energy metabolism and respiration. Insufficient iron intake can lead to serious health problems, including iron-deficiency anemia. TMPRSS6 is a gene in our body that facilitates iron absorption. People with certain types of this gene may not be able to absorb iron efficiently and, thus, may need more iron either through dietary sources or supplements.
Magnesium is the fourth most abundant mineral in your body. It plays a role in over 300 enzyme reactions in the human body. Magnesium helps in maintaining normal nerve and muscle functions. It is also essential for regulating blood glucose levels and producing amino acids. About 48% of Americans fall short when it comes to daily magnesium intake. Some contributors to magnesium deficiency are type 2 diabetes, age, alcoholism, and chemotherapy. People with certain genetic types may also need more magnesium in their diet or as supplements to compensate for the loss during entry, absorption, or circulation of magnesium.
Calcium is essential for maintaining the strength and structure of bones and teeth. It plays a vital role in certain metabolic functions. An adequate level of calcium in the body over a lifetime can help prevent osteoporosis. Calcium levels are tightly regulated by two main hormonal systems, i.e., parathyroid and vitamin D, which themselves are influenced by genetic factors. Any changes in these genetic factors can lead to higher or lower than normal calcium levels in the body, both of which are dangerous. People with these genetic types may either need to increase or decrease calcium consumption.
Selenium is an essential mineral and thus needs to be obtained through dietary sources. It is a trace mineral that helps synthesize antioxidant enzymes, maintain fertility, and support a healthy immune system. There are also some ongoing studies investigating its role in cognitive health and cancer risk. Not having enough selenium in your system can cause several health problems, including a weakened immune system and infertility. It may also contribute to depression, anxiety, and dementia. People with certain genetic types may be at risk for selenium deficiency due to inefficient absorption of the mineral and may benefit from selenium supplementation.
Antioxidants play a crucial role in reducing the ill effects of free radicals in the body. Free radicals are compounds whose high levels are harmful to the body. By fighting the free radicals in the body, antioxidants prevent premature aging, tissue damage, and the onset of chronic diseases. Antioxidants are present in vegetables, fruits, cereals, green tea, etc. The body also produces some antioxidants - these are called the endogenous antioxidants. People with certain genetic types produce a lower amount of endogenous antioxidants and may need to include more antioxidants in their diet to meet the requirements.
The preference for sweet taste is genetically influenced. A variant in the TAS1R2 has been associated with lower sugar sensitivity and higher sugar intake among overweight individuals. This variant is also associated with a preference for sweet foods. Studies have suggested that this can be due to a lowered sensitivity to sweet taste caused by a reduction in the number/sensitivity of the sweet taste receptors. People who prefer sweet foods also tend to consume high-calorie foods. This can cause insulin resistance, leading to weight gain and other health conditions like diabetes, heart diseases, and high cholesterol levels.
Fats are essential to our diets. According to research, the tendency to prefer fatty foods has a genetic basis. While fat is universally palatable to humans, the fat perception between different individuals tends to differ. CD36 gene is associated with fat intake and obesity by influencing the sensitivity to and preference for the fatty taste. People with certain genetic types may find fats creamier and more enjoyable than others and, thus, over-consume them. This can increase the risk of developing obesity and other health conditions. These individuals can maintain their health by being aware of their genetic tendency and monitoring their fat consumption.
The evolution of bitter taste likely occurred as a defensive and protective method to prevent species from ingesting potentially poisonous foods. The bitter taste is recognized by receptors formed by the TAS2R gene family. Around 25 such receptors in our tongue detect different bitter molecules. These receptors bind to the phytochemicals (chemicals present in plants) to sense the bitter taste. People with certain genetic types tend to avoid bitter vegetables due to a heightened sensitivity to the bitter taste, thus also avoiding some benificial but bitter veggies. The differences in bitter taste perception are due to genetic variations in taste receptors.
Caffeine is a central nervous system stimulant and the most widely consumed psychoactive drug. If you are a fast metabolizer of caffeine, increased caffeine consumption can bring some health benefits to you. The fast metabolizers tend to consume >4 cups (>625mg) of caffeine per day. However, if you are a slow metabolizer, you may not want to consume more coffee, as caffeine persists in your body for a longer period of time. Increased caffeine consumption by slower metabolizers may result in negative side effects like insomnia, anxiety, and increased risk of heart diseases.
Caffeine metabolism primarily takes place in the liver. A group of enzymes called the P450 enzymes are responsible for metabolizing 90% of caffeine. Any change in the gene responsible for the production of these enzymes can affect the metabolism of caffeine. People with the "slow-metabolizing" gene type may be at higher risk for heart disease upon high caffeine intake. On the other hand, the "fast-metabolizing" gene type may allow you to consume a higher amount of caffeine without experiencing any side effects. Several non-genetic factors like diet, smoking habits, liver disease, and some medications can affect caffeine metabolism as well.
Research estimates that 18 million Americans have gluten sensitivity. It is characterized by adverse reactions to gluten, a protein found in wheat, barley, and rye. People who are sensitive to gluten may experience common symptoms like bloating, diarrhea, fatigue, headaches, brain fog, joint pains, upon consumption of gluten. Some genes, especially the HLA gene family, contribute to the risk of developing gluten sensitivity. People with certain genetic types of the HLA gene family may be at a higher risk for gluten sensitivity. Upon further confirmation, the best way to go forward is opting for a gluten-free diet.
Lactose intolerance, a common digestive problem, is characterized by a person's inability to digest a natural sugar 'lactose' present in dairy products. An enzyme, lactase produced in the small intestine, breaks down the lactose sugar. When there is a deficiency of this enzyme, the undigested lactose moves from the small intestine into the large intestine, where the bacteria present interacts with the unprocessed lactose sugar and causes the symptoms of lactose intolerance like bloating, gas, and diarrhea. People with certain genetic types may have less or no lactase enzyme and are thus more prone to developing lactose intolerance.
Alcohol flush, commonly called the "Asian Glow," is a condition where a person develops red patches across the face, neck, and shoulders upon alcohol consumption. This happens when the enzyme that digests alcohol does not function properly. People who carry the gene responsible for this "faulty enzyme" are at a higher risk for alcohol flush. The only way to avoid an alcohol flush reaction is to avoid or limit your alcohol consumption. This is recommended for people who don't experience alcohol flush as well. According to the World Health Organization (WHO), alcohol is responsible for more than 5 percent of deaths worldwide.
Weight gain, weight loss, and weight management all have a significant genetic aspect to them in addition to the diet and lifestyle aspects. The genes that control metabolism, energy storage, and energy expenditure influence the amount of calories stored and spent. Thus, influencing weight loss/gain in the body. While storing calories offered a survival advantage to our ancestors during leaner times, it has now become an undesirable aspect in the era of surplus food availability. People with certain genetic types tend to store more calories and expend less of them. This can result in a higher tendency to gain weight.
Carbohydrates are your body's main source of energy. There are three types of carbohydrates that include starches, fiber, and sugars. Starches are referred to as complex carbs, while sugars are the simple carbs. In general, it is recommended to consume 45-65% of the total calories through carbohydrates. People with certain genetic types tend to gain more weight upon consuming carbohydrate-rich foods than others. These individuals can maintain their weights by reducing the amount of carbs in their diet. Complex carbs like fruits, vegetables, nuts, and whole grains are considered to be better for the body than simple and refined sugars.
Saturated fatty acid (SFA) is a type of dietary fat that isn't considered healthy. These fats are solid at room temperature. The main sources of saturated fats include cream, cheese, coconut oil, palm oil, beef, and lamb. A high intake of SFA is associated with an increase in the low-density lipoprotein or the LDL cholesterol levels (the "bad cholesterol") in the body. People with certain genetic types tend to gain more weight upon consuming SFA-rich foods than others. These individuals can benefit in terms of weight management by reducing the amount of saturated fats in their diets.
Monounsaturated fatty acids (MUFA) are one of the "healthy fats." They include omega-7 fatty acids and omega-9 fatty acids. They are associated with anti-inflammatory properties, lowering blood pressure, and maintaining triglyceride levels. In fact, the American Heart Association (AHA) recommends replacing the SFA and Trans fats in your diet with MUFAs. Some MUFA-rich foods include olive oil, nuts, legumes, berries, avocados, whole-grain wheat, and nut butter. However, people with certain genetic types tend to gain weight upon consuming excess MUFA-rich foods than others. These individuals can benefit in terms of weight management by adjusting the amount of MUFA in their diets.
Polyunsaturated fatty acids (PUFA) are one of the "healthy fats" that include omega-3 and omega-6 fatty acids. Some dietary sources of PUFAs are walnuts, fish like salmon and trout, sunflower seeds, and soybean oil. Omega 3s are important for brain and heart health as they reduce blood pressure and triglyceride levels. Omega 6s help in maintaining bone health and stimulating hair growth. However, people with certain genetic types tend to gain weight upon consuming excess PUFA-rich foods than others. These individuals can benefit in terms of weight management by adjusting the amount of PUFA in their diets.
Dietary fiber is found in whole grains, vegetables, fruits, and legumes. A high-fiber diet keeps you fuller for a longer time. It normalizes bowel movements, helps with weight loss/maintenance, lowers cholesterol levels, and also reduces the risk for health conditions like diabetes and heart diseases. Getting your fiber from food sources is recommended rather than taking supplements. Soluble fibers (dissolves in water) can help with weight loss in the abdominal area. Some foods containing soluble fiber are avocados, sweet potatoes, broccoli, pears, and kidney beans. People with certain genetic types lose more weight than others on high fiber intake.
Proteins are building blocks of life. They are present in every cell of the human body and are crucial for development and maintenance. Proteins also reduce appetite and curbing cravings. This occurs because of a drop in the hunger hormone ghrelin upon consumption of protein. Protein-rich foods also help in speeding up your metabolism. Studies have found that eating protein for breakfast can help with a quicker weight loss. Protein intake at around 30% of calories seems to be optimal for weight loss. People with certain genetic types tend to experience greater weight loss on a protein-rich diet than the others.
Weight regain after successful weight loss is a major problem for many individuals. According to a study, over 75% of obese subjects fail to maintain their weight following weight-loss interventions. The genetic influence on weight gain can be as high as 70-80%. This can be because of some gene variants that predispose an individual to obesity and high BMI. People with such genetic types tend to regain weight quickly after experiencing weight loss. These individuals need to adhere to exercise continually. Recalculating your calories and updating your diet plan post-weight loss may also protect you from regaining those pounds.
The changes in blood pressure that occur when there's a change in dietary salt intake vary from person to person. The American Heart Association (AHA) recommends no more than 2300 mg of salt per day. However, on average, most people consume 3400 mg of salt per day, with a lot of it coming from processed foods. People with certain genetic types may have higher blood pressure in response to high salt consumption. About 60% of people with high blood pressure are thought to be salt-sensitive - which means their blood pressure increases upon consumption of a high-salt diet.
Riboflavin, also known as vitamin B2, is a water-soluble vitamin. It helps the nerves and brain function properly. Riboflavin is also required for healthy skin, hair, eyes, and liver. The MTHFR gene has been shown to influence the blood pressure response to riboflavin intake. People with a certain type of the MTHFR gene can significantly lower their blood pressure and, in turn, their risk of heart disease and stroke by increasing their intake of vitamin B2. Such individuals can benefit greatly by consuming vitamin B2-rich foods like eggs, mushrooms, spinach, avocados, broccoli, and red meat.
Homocysteine is an amino acid in your blood. It is synthesized in your body, as well as obtained through food sources. The buildup of this amino acid is harmful to the body, a condition called hyperhomocysteinemia. Homocysteine is converted into either cysteine or methionine, amino acids that are safe and useful for the body. Hyperhomocysteinemia is linked to an increased risk of cardiovascular diseases, certain types of cancer, and bone disease. Variants in genes like MTHFR, BHMT, and MTR, influence the risk of homocysteine buildup.
Coenzyme Q10 (CoQ10) is a type of coenzyme and natural antioxidant found in all cells of the body. It aids enzymes in various body functions, from food digestion to muscle repair and more. It plays a major role in mitochondrial bioenergetics and is responsible for generating more than 95% of the body's energy. Research shows that CoQ10 supplementation can improve power, recovery after exercise, reduce oxidative damage, and increase energy. Variants in the NQO1 gene influence the amount of CoQ10 produced and utilized by the body.
Alcohol dependence (AD) is defined as the use of alcohol in larger amounts or for prolonged periods. AD can be a substantial burden to your health and economy. Heavy alcohol drinking is correlated with increased mortality and risk of various health disorders like chronic liver disease, stroke, heart disease, etc. It can also affect your mental health, interpersonal relationships, and financial status. AD is influenced by various environmental factors and genetics (through regulation of alcohol metabolism). People with certain genetic types are associated with a higher risk of alcohol dependence. They may exhibit signs like experiencing temporary blackouts, choosing to drink over other responsibilities, feeling hungover when not drinking or drinking alone or in secrecy.
Bone-mineral density (BMD) is a measure of mineral content, especially calcium, in your bones. BMD tests are used predominantly for the detection of osteoporosis, a condition characterized by weak and brittle bones. Osteoporosis is the most common bone disease. Several factors, such as age, sex, disease, genetics, and lifestyle, can affect BMD measurements, and normative standards must be applied for specific groups and individuals. Certain genes like VDR and FGF2 have been associated with BMD. People with certain variants of these genes may be at an increased risk of lower BMD.
The Mediterranean diet typically involves daily intake of fruits, vegetables, healthy fats, occasional consumption of fish and poultry, and limited dairy and red meat intake. It is recognized by the WHO as a healthy and sustainable dietary pattern. Numerous studies have shown that the Mediterranean diet can help with weight loss and preventing heart attacks, stroke, type 2 diabetes, and premature death. FTO is one of the genes that has been extensively studied for its effects on obesity and weight gain/loss. People with certain variants of this gene may experience more weight loss on the Mediterranean diet than the others.
Body mass index (BMI) is an estimate of body fat based on height and weight. The BMI is a method used to broadly categorize a person as underweight, normal weight, overweight, or obese based on tissue mass and height. Several factors, such as age, sex, disease, genetics, and lifestyle, affect BMI measurements, and normative standards must be applied for specific groups and individuals. BDNF is one among several genes that are studied for obesity. It produces a growth factor in the brain. Certain variations of this gene promote excessive weight gain. In fact, some of these variants are used as markers for obesity
Omega-3 and omega-6 fatty acids are a type of healthy fats called polyunsaturated fats. This type of fat is produced in the body and needs to be supplemented through diet as well. Polyunsaturated fatty acids (PUFAs) play important roles in health and disease. PUFA levels are influenced by nutritional and genetic factors. The PEMT and MTHFR genes are associated with the levels of PUFAs in red blood cells. The FADS2 gene influences the desaturation (degradation) of PUFAs. Certain variants of these genes result in lower PUFA levels by influencing its absorption and desaturation in the body.
Nicotine is a highly addictive chemical that is commonly found in tobacco. Upon consumption, nicotine stimulates the release of neurotransmitters like dopamine in the brain, which trigger the feeling of pleasure. Habitual smoking may result in nicotine dependence, which can make it hard to quit this habit. A person may also experience withdrawal symptoms when trying to quit due to the sudden drop in the neurotransmitter levels. A family history of nicotine dependence can put you at risk for it. Certain genes like CHRNA5, NRXN1 have also been implicated in nicotine dependence risk.
Adiponectin is a protein hormone secreted primarily by adipocytes or fat cells found in the adipose tissue. In rare cases, it is secreted by muscle and brain cells as well. During pregnancy, the placental cells also secrete adiponectin. This hormone plays a role in the metabolism of lipids and glucose. Reduced levels of adiponectin (hypoadiponectinemia) are associated with health conditions like hypertension, insulin resistance, elevated triglyceride levels, type 2 diabetes, stroke, and coronary artery disease. The ADIPOQ gene contains instructions for producing this hormone. Certain variants in CMIP, ADIPOQ genes can influence adiponectin levels.
Snacking helps bridge the hunger gap between two meals. It helps curb your appetite and control your meal portion sizes. However, the wrong snack choices or snacking too frequently can lead to overconsumption of calories during the day. This could lead to weight gain. Fiber-rich snacks twice or thrice a day are ideal. Foods rich in fat, sugar, and salt can lead to health problems like obesity if consumed regularly. MC4R is a gene that has been studied to modulate eating behavior. Certain variants of this gene can increase your risk of weight gain via frequent snacking.
Cilantro or coriander is a herb commonly used in cooking. Most people like the taste of this herb, but it has been reported that for a certain group of people, it tastes like soap and dirt. This is due to the presence of several aldehydes in them. Cilantro preference seems to have a genetic component to it. Olfactory-receptor genes influence our sense of smell, which directly alters our taste perception. OR6A2 is one such gene that, in particular, seems to have a high binding affinity to the soapy-flavored aldehydes. People with certain variants of this gene may have an aversion to cilantro.
