Nowadays many genetic labs (providing home DNA testing kits) claim that they can recommend a personalized diet and optimal nutrition plan to lose and manage your weight based on your DNA. However, the question is how these DNA test kits work? Moreover, are they beneficial to stay fit? Here, I am providing you everything you need to know about nutrition DNA testing (Nutrigenetics).
How does our DNA determine our response to food?
The information hidden in our genes regulates our metabolism, food senses, eating behavior, and sports capabilities.
Daily, we consume micronutrients (including vitamins and minerals) and macronutrients (such as fats and carbohydrates). Our body utilizes these nutrients with breaking down and transforming them into the chemical compounds that our body needs depending on specific enzymes. The function and efficiency of these enzymes to utilize the nutrients is regulated by our genes.
Hence variations in your DNA may make you prone to gaining weight or obesity. Perhaps you have noticed some people do not succeed to lose weight despite their best effort, while others can eat whatever they wish and be still thin. Furthermore, due to DNA variations, each person could respond to a specific diet differently.
What does Nutrigenetics mean?
Nutrigenetics is a science to understand the association between genes variations and dietary response as well as the role of genes in the determination of nutritional requirements and metabolism. Specifically, their researches aim to suggest dietary changes that could prevent or reduce obesity.
However, research into how our DNA affects metabolism and our weight is a relatively new field. Moreover, our understanding of the list of genes and DNA variations contributing to metabolic pathways and eating habits is limited. However, in recent years, scientists succeed to find associations between certain genes and DNA variations with food metabolism, weight tendency, and muscle strength. In turn, DNA labs can provide personalized advice on diet and exercise plans which fit the individual’s genetic make-up.
How do home DNA testing kits work? Moreover, which genes are tested?
DNA labs providing home DNA test kits analyze certain DNA variations in particular genes. Generally, these DNA tests evaluate nutritional needs (vitamins and minerals requirement), metabolic rate, food reactions (to alcohol, caffeine gluten, and so forth), weight loss response (effectiveness of low fat or low carbohydrate diets), the ability for weight loss and eating behavior. However, some DNA testing kits may analyze all of the features mentioned above, and some might check only some of them.
Example of tested genes for Weight loss diet
- As an example, the FTO gene, a fat mass and obesity-associated gene has been highly associated with an increased risk of obesity and a higher BMI (Body Mass Index). Certain FTO gene variations may facilitate weight gain in humans by shifting the endocrine balance from the appetite-reducing hormone leptin toward the hunger-promoting hormone ghrelin. Hence, the FTO variant confers a predisposition to obesity and may play a role in the control of food intake and food choice. In the case you have predisposing FTO variation, you can get recommendations on how you can plan to eat and control cravings.
- Variation in the TFAP2B gene is another diet-related gene variation. For instance, people with the DNA variation AA in TFAP2B have a better response to a diet with low fat and high in complex carbohydrate for losing weight. Though, people with DNA variants GG and AG have a better response to weight-loss diets with a higher amount of unsaturated fats and less intake of carbohydrates. Hence DNA tests can suggest you which dietary plans work best for you based on your DNA.
- Furthermore, DNA tests may determine your eating behavior by analyzing the genes contributing to flavors senses and food taste. Since genetics influences taste, affects the selection of meal size, food preference, and meal timing. However, you should remember that eating behavior is not only based on our genetic, but it is a complex interplay of physiologic, psychological, social, and genetic factors.
Examples of tested genes for personalized nutritional needs
As I mentioned above, genetic variations are important determinants of nutrition requirements.
- As an example, the metabolism of folic acid (vitamin B9) is regulated by the MTHFR enzyme. A gene variation replacing nucleotide C to T in MTHFR gene leads to metabolic changes that cause risk of cardiovascular diseases and neurological problems including memory problems, anxiety, fear, depression or irritability. The metabolic abnormalities because of gene variations in the MTHFR gene can be modulated by increasing folate intake. Hence, the folate requirements are different in affected individuals (TT variations) relative to normal people (CC) or heterozygous individuals (CT).
- Furthermore, there is inter-individual response differences to vitamin D and Ca supplementation based on genetic make-up. Subsequently, DNA tests can suggest suitable supplements in their correct amounts.
Nutrition DNA testing for the well-being
- DNA tests evaluate your response to foods, such as caffeine, alcohol, gluten. Consequently, you can be aware which foods are right for you and which foods you should avoid for well-being.
- Also, physiological response to exercise and likelihood of a certain sports benefits varies considerably among individuals based on their DNA. Then DNA tests help you to understand what exercise and fitness plans are best for you to maximize your potential.
What are the best DNA testing kits?
Notably, different DNA testing kits may analyze a different number of genes. The more genes are tested, the more reliable and appropriate are the results for managing weight and being fit. You should carefully review the genes that DNA labs promise to test.
Once your DNA has been tested, and your gene variations are determined, DNA labs can provide you with the information and actionable advice to have dietary regimes and exercise plans to manage your weight and have a healthy lifestyle.
Last but not least, Nutrigenetics requires a deep understanding of nutrition, genetics, and biochemistry; it is often difficult to read, understand and interpret Nutrigenetic results. Hence, only well-educated health professionals can interpret the results to be applied for health and fitness.
Above all, the list of genes and DNA variations contributing to weight loss and weight management is still needs to be completed. Then you do not receive a comprehensive and all-inclusive result after sending your samples (your saliva or mouth swab) for DNA testing. However, you will get some valuable insights about your genes, body, and physiology to improve your health and your weight management.
– International Society of Nutrigenetics / Nutrigenomics. http://www.nutritionandgenetics.org/
– Eleanor R. Grimm and Nanette I. Steinle. Genetics of eating behavior: established and emerging concepts. Nutr Rev. 2011 Jan; 69(1): 52–60. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3052625/)
– Michael Fenech, Ahmed El-Sohemy, Leah Cahill, et al. Nutrigenetics and Nutrigenomics: viewpoints on the current status and applications in nutrition Research and Practice. J Nutrigenet Nutrigenomics. 2011 Jul; 4(2): 69–89. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3121546/)
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