When the human genome was first sequenced, some people optimistically assumed that we now (or soon know) all about human genes and would be able to predict who would develop a disease and describe what each individual should do to ensure the best possible health. These expectations were not fulfilled. The science is complicated.
Several companies have recently offered to scan your genome and find out what you should eat based on your DNA. GenoPalate is typical. He. She Promises to tell you:
- Your optimal blend of macronutrients to determine the basis for a healthy diet
- How much of each micronutrient would your body benefit the most?
- What are more than 100 types of foods that suit your nutritional needs
- How your body reacts to substances including alcohol, gluten, caffeine and lactose.
- How to make decisions at the grocery store, eg buying brussels sprouts or broccoli
Under the tab “We know” They included 10 studies as examples of those they relied on for their recommendations. This may seem “science” and impressive at first glance, but most studies have been inconclusive, preliminary, or irrelevant to the company’s claims. One thing glaringly missing is any study that tests whether people who follow the company’s DNA-based diet recommendations are in any way healthier than people who follow standard, evidence-based guidelines for a healthy diet.
When one woman’s DNA-based diet and exercise recommendations arrived, she was frustrated.
Although she was “personal” based on her DNA, she seemed vague and unworkable. For example, the evaluation indicated a “high sensitivity” of carbohydrates. “The genes in this panel influence the way refined carbohydrates are metabolized and absorbed, and the combined effect of your variables puts you in a slightly increased influence, meaning you’re less positioned to deal with excess carbohydrate intake than most people,” the report states. .
According to the researchers, there’s a reason the ‘personalized’ diet plans promoted by these wellness companies are filled with generalized scientific jargon and loose recommendations that don’t make promises: There isn’t enough evidence yet for personalized gene-based diet plans.
Some things to keep in mind:
- The foods we eat are a mixture of complex ingredients.
- Genetics is more complex.
- Genes are affected by other genes.
- Genes can be turned on or off by other genes and environmental factors.
- The association between a genetic variant and disease in a population does not mean that an individual with that variant will develop that disease.
- DNA can be faulty; It might predict that a brown-eyed person should have blue eyes.
- Different companies often make different recommendations for a DNA-based diet.
- Identical twins may have different responses to the same foods.
These companies blend half-baked insights from genetic research with standard nutrition and lifestyle guidelines that are available elsewhere for free. Companies charge anywhere from hundreds to thousands of dollars.
Bottom line: Not based on good science
Are you sick and tired of people telling you what to do and what to eat? I know I am! They all disagree with each other and do not provide reliable scientific evidence. As for me, I will continue to eat a variety of foods that taste good, and follow the general advice of nutritionists who agree with each other about the current science.
One of the first things I looked at, working with Stephen Barrett on Quackwatch, was Questionable genetic test. We quoted an expert whose words are as true today as they were in 2008:
For most people, adapting your diet to your genetic makeup is as scientific as adapting your diet to your star sign.