Personalized nutrition is a concept that empowers each individual to seek out foods specific to his or her needs based on genes, lifestyle, and microbiome. It’s an intuitive idea. You wouldn’t settle for the same outfit everyone is wearing or listen to the same music. So why would you choose to eat the same?

Well, recently Harvard set out to prove the obvious. In an ambitious project surveying 700 sets of identical twins, preliminary results have shown that, in fact, different people respond differently to the same diet. Here are some of the most powerful determinants of your ideal diet.

Genotype

Personalized nutrition based on genotype is a field of scientific research called nutrigenomics. But nutrigenomics isn’t just the province of elite athletes or the ultra rich. It’s quite common. Lactose intolerance, for example, could be discovered within an infant’s genome before the child ever got a chance to get sick from an ice cream cone.

Some genetic considerations on your diet come from what groups you’re in. For example, older women face bone density issues and should therefore consume calcium. People from Mediterranean countries may encounter thalassemia, which can be treated with increased iron intake. So consider what “clubs” you’re in when considering your diet.

With personalized assessment and the proper nutritional remedy, some disorders can even be prevented from manifesting. For example, even if you have a genetic inclination towards diabetes, the disease can be prevented or delayed by eating fiber avoiding unhealthy fats and sodium along with some exercise. The same can be said of other genetic disorders such as obesity, coronary heart disease, and alcoholism.

Genes are not destiny. The field of epigenetics has proven that environmental and behavioral factors affect gene expression. For example, several studies have shown that malnourished mothers give birth to children with diabetes and a tendency to overeat. So epigenetics can affect nutrition but the reverse is true as well. Nutrition can affect epigenetics. For example, certain foods such as Polyphenols found in green tea and resveratrol found in grapes, can influence how your genes express themselves and lower your risk of developing cancer. Epigenetics is a sort of bridge between genetics and lifestyle.

So eat well. You’re eating for your grandchildren’s health!

Lifestyle

Genetics only goes so far to explain one’s health. In Harvard’s, 2019 study of 700 identical twins, researchers discovered that genetics only accounted for about a third of certain health consequences such as insulin responses to diet. Lifestyle plays a tremendous role in customizing your diet. For the sake of simplicity, let’s divide lifestyle into: eating habits, exercise habits, and sleeping habits.

1. Eating Habits: Much of nutritional advice is universal. Such advice includes: eat a well balanced diet, maintain portion control, don’t skip breakfast, stay hydrated. While the details may vary, the nutrients you should prioritize are fiber, protein, vitamins, whole grains, and avoid excessive sugar, fats, and alcohol.
   
   But some aspects of nutrition may be customizable depending on your eating habits. For example, perhaps mindless eating throughout your workday is impossible to avoid. If so, consider only bringing sugar snap peas and popcorn to work. This also works if you have a penchant for crunchy textures. The key is harm reduction and sustainability. You can’t always be the best, but you can always be better.
2. Exercise Habits: Exercise. For some, it’s a hellish torment. For others, it’s a dopamine fueled diversion. And for others still, it might be both of these things depending on whether they’re winning or losing the game. Whether it’s a big part of your life or a minor distraction, it’s important to remember your nutrition for exercise is different than resting nutrition.
   
   If you’re inclined towards high intensity workouts, sprints, or short bursts of weight training, you may be favoring fast twitch muscles and want to consider proteins as well as vitamins C, D, and E. Endurance and cardio-based workouts like jogging or biking favor slow-twitch muscles which can burn fats as well as carbohydrates.
   
   Another highly personalized aspect of nutrition is the timing of meals before or after a workout. The rule of thumb may just be to monitor your blood sugar levels to determine when is best to eat. Here’s a primer on fitness and blood sugar levels.
3. Sleeping Habits: Personalized nutrition may improve sleep problems and sleep problems may prove to be the culprit behind your less-than-ideal nutrition. Hopefully this is not news to you but eating sugar or caffeine right before you go to bed is probably not the best idea. The worst invention in the world is dessert. Who invented this custom of serving highly sugary confections at the very end of a day? Save your desserts for earlier in the following day!
   
   But then there are the less obvious considerations. For example, are you getting enough magnesium in your diet? Magnesium promotes better sleep. So can melatonin tryptophan, b complex vitamins, Omega-3 and Vitamin D.
   
   Sleep and nutrition can work as a virtuous cycle. Better nutrition leads to better sleep. Better sleep leads to better nutrition choices the next day!

Microbiome

Pregnant women are said to be “eating for two.” But in reality, at any given moment all humans are eating for thousands of organisms within our microbiomes. In fact, more than half the cells in your body are not human cells, but bacteria. These microorganisms, including fungi and archaea as well, live in the digestive tracts of humans, helping out with digestion.

Dietary nutrition and timing, including seasonality, circadian rhythmicity and intermittent fasting, shape the gut microbiome composition and function. The microbiome itself affects digestion, the absorption of nutrients, and the shaping of the mucosal immune response.

The microbiome is mostly a product of environmental factors rather than genetic and nutrition is probably chief among those environmental factors. But the microbiome may have the most individualized response to nutrition of any system. This hyper-individualized response may be key to identifying the correct nutritional response to genetic data. One subject found that while he was genetically predisposed to diabetes, an analysis of his microbiome revealed he did not have to bid goodbye to bagels. “It turns out those little bugs in my guts seem to like bread, if it’s combined with fats and proteins,” he says. Somehow, his gut was ordering him to eat his bagel with cream cheese and lox in order to keep his blood sugar levels steady.

There seems to be one universal nutritional takeaway: Diverse food inputs lead to a diverse microbiome, which tends to be more resilient. Perhaps the biggest myth to bust is that of the cult of probiotics. There’s no conclusive evidence that probiotics have beneficial impacts on the microbiome.

Now, analysis of your microbiome is one stool sample away. You contain multitudes. It may be time to learn more about those multitudes.

The Power of Personalization

Personalized nutrition is a revolutionary concept that may rapidly democratize healthcare and propel us into a new era of longevity. Its applications in the field of pregnancy may lead to a new generation of super-healthy, super-intelligent humans. We may not all be sharing the same diet but we will share in the same prosperous new world, savoring the fruits of our labor.

Joseph Conrad once said, “we live as we dream- alone.” He may well have added, “and that’s also how we choose what to eat.”

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