Who would ever think that one change the DNA of a gene could affect what you like to eat, what you can eat, what tastes good to you, does your body benefit from your diet, or “foods” that can be addictive, and how much benefit you actually get from our vitamins? What a difference a base-pair in our genes can make! This one base-pair difference is called a ,Single Nucleotide Polymorphism, abbreviated as SNP. and pronounced SNiP.
There are 34 of these SNPs that have been well characterized and documented. This post will review how these SNPs act and in subsequent posts, you’ll learn which SNPs are responsible for that characteristic.
Digestion & Absorption. Whether your body benefits from the foods you eat or not and by how much depends on whether those fats and carbohydrates are absorbed in you gut. Much of digestion, and especially absorption, is affected by your genes. A gene that reduces the speed of carbohydrate processing may lead to the development of type 2 diabetes, obesity or metabolic syndrome.
Food Intolerance. Almost all of us all have foods that just don’t agree with us. You don’t know why, but you just avoid that food because it is unpleasant. Some of this is also because you don’t have the right genes for that food, an example is lactose intolerance.
Vitamin Processing. Vitamins, whether you take them as a supplement or as part of your diet, play an important role in health and well-being. It is very hard to know if you’re getting the vitamins you need. If you know your genes, you may also know if you have a SNP that affects a specific vitamin and how it is processed by your body. Vitamins affected by genes include vitamin A, vitamin B6, folic acid, and vitamin D.
Taste Sensation. Some of our key tastes, salt, sugar and bitter are under genetic control There are four areas of the tongue that give us the sensations of: bitter, sour, sweet and salt. Three of these have SNPs affecting how your food tastes. It also accounts for why your tastes may differ from your friends or family. Some people love cilantro and others hate it.
Eating Preferences. Are you feeling full and satisfied after a meal? SNPs are at work here as well. Some of these genes are involved in over-eating and over-drinking to reach a state of feeling good. You can thank a dopamine SNP for these differences.
Food Addiction. The primary “foods” you can become addicted to are nicotine and alcohol. The faster your body processes alcohol, the quicker you feel its nasty effects and naturally, you stop drinking. However, if you’re one of the slow processors then it takes much more alcohol to feel an effect and easier to drink to excess.
Where do you go to get information about your SNPs? There are many different direct-to-consumer genetic testing services available. The New York Times suggests: https://www.nytimes.com/wirecutter/reviews/best-dna-test/ The primary source for this article is available at: https://pubmed.ncbi.nlm.nih.gov/32230794/
Disclaimer: I did my post-doctoral fellowship in Human Genetics. I am not a physician and for medical advice, please seek the expertise of a healthcare professional.