Nutrigenomix offers dietary guidance based on saliva-based DNA tests. Some experts say you can’t decide which food is best from information in a DNA test.

From fad diets to surgeries, Americans are constantly seeking the newest “cure” to what ails us.

In fact, we spend billions of dollars each year searching for this key to health and happiness.

The weight loss business alone spurs countless diet plans, books, apps, shakes, pills, and more.

It’s no wonder, then, that every time a new solution shows up on the health stage millions flock to it for answers and guidance.

Like many health and nutritional options before it, one of these newest solutions, DNA testing, is raising eyebrows.

DNA testing has been increasingly popular in recent years as a way to understand your genetics, your family history, and your origins.

But can these DNA tests be used for so much more?

What if, in addition to telling you where you’re from or that you’re related to a famous historical figure, your genes could be used to make you healthier today?

That’s exactly what Ahmed El-Sohemy, the founder and chief scientific officer of Nutrigenomix, says his product can do.

Nutrigenomix uses nutrigenomic testing to provide you detailed dietary information based on your DNA.

Nutrigenomics is the area of science that looks at the effects of food on gene expression. In other words, these tests can tell you how your unique set of 23 pairs of chromosomes determines what you should and shouldn’t eat.

“We have known for a long time that some individuals respond differently from others to the same foods, beverages, nutrients, and supplements they consume. That is, a one-size-fits-all approach to optimal nutrition is ineffective,” El-Sohemy told Healthline.

“We now know that genetic differences — variations in the sequence of a gene — can explain some of these different responses. We wanted to provide tests consisting of genetic markers related to several important lifestyle factors, including weight management and body composition, nutrient metabolism, eating habits, cardiometabolic health, food intolerances, and physical activity.”

Skeptics, however, say a DNA test might reveal gene variants, but they’re not a source of reliable nutritional advice.

“When companies use the nutrigenomics model for ‘food sensitivities,’ that’s when I get a bit hesitant to accept all the science based on individual screenings,” Stella Metsovas, a clinical nutritionist and author of “Wild Mediterranean,” told Healthline. “It’s still too complex of a science to apply overall, especially when lifestyle factors are concerned.”

Some of these DNA tests use blood samples, but many products like El-Sohemy’s Nutrigenomix rely on saliva tests because they’re convenient.

Plus, human spit contains all the genetic material testers need to produce your detailed DNA nutritional map.

Once the sample is collected, the test is shipped back to the companies.

In several weeks, you’re sent a packet of information about your specific genetic markers — a guide to your nutritional DNA makeup.

“Clients are often surprised by the number of genetic markers available to guide dietary choices beyond macronutrients such as fat and protein,” El-Sohemy said. “We can determine what type of fat an individual is most likely to benefit from in terms of weight loss and cardiometabolic risk.”

Once you have the results, you can decide what you do with them.

Some companies, like Nutrigenomix, require clients to work with a doctor in order to interpret the results and apply them to their daily food choices.

“We believe that providing our service through a qualified healthcare professional is the most responsible and effective way to communicate this type of health information,” El-Sohemy said. “A healthcare practitioner — a doctor, dietitian, etc. — works alongside a client to interpret and communicate their individual test results. Together, they create goals to mitigate risk of nutrient deficiencies and optimize body composition. As one-size-fits-all approaches tend to be impractical, this approach allows a trained healthcare professional to work closely with their client to ensure that their dietary goals are met.”

If the results show you’re sensitive to starch, you might cut out potatoes, corn, and other starch-heavy foods.

If the results show you’re sensitive to saturated fat, you might limit your intake to lower your risk for cardiovascular health issues.

“Due to the variety and number of genes tested, clients can also prioritize which goals to address first, such as reducing sodium to lower their risk of high blood pressure. And once they are able to adopt these strategies successfully, new goals can be made based on other genetic risks they have,” El-Sohemy said.

Unlike books or apps, nutritional DNA tests wear a hefty price tag.

Each test can set you back several hundred dollars, and you may need to partner with a doctor or genetic coach in order to decipher the results. That’s even more money out of pocket.

Athletes are among the many clients for these nutrigenomics companies. With a greater emphasis on athlete performance through dietary approaches, DNA nutrition tests can help athletes and coaches find new ways to maximize performance.

People facing mysterious dietary challenges are also turning to these tests.

When typical allergy tests and elimination diets provide no insight, these DNA-based nutrition tests may be a last-resort option for people looking for answers to undiagnosed problems.

Metsovas doesn’t believe the average person should be forking out the dough for these tests just yet, however.

“DNA companies refer to these tests as ‘personalized dietary advice,’ which stems from the theory that human needs vary considerably from diet to diet,” she said. “For example, ketosis might work wonders on Jane, helping regulate insulin levels and thereby [helping her with] losing weight, while maintaining lean muscle tissue. Susie might respond unfavorably due to various health factors such as hypothyroidism, an indication that there might be other issues in the body, including the microbiome.”

“The tricky part of the model is that your lifestyle plays a huge role on how your genes are expressed,” she added.

The Academy of Nutrition and Dietetics said in a statement regarding these tests, “The use of nutrigenetic testing to provide dietary advice is not ready for routine dietetics practice.”

A study in the British Medical Journal found that people who knew their DNA-based health risks were no more likely to change their dietary behaviors.

For her part, Metsovas says a microbiome analysis is the way to go before you pick up a DNA kit.

However, this type of testing faces a great deal of skepticism by many in the medical community, too.

“Keep in mind this is a test for genetic modifiers of diet,” El-Sohemy said. “The test we developed does not diagnose or predict the likelihood of developing any disease. But, it does tell an individual how they respond to various aspects of their diet.”