It has become obvious that there is a great deal of biochemical individuality when it comes to how people respond to different foods, supplements, exercise programs, and medications.
To achieve and maintain optimal health, you need to get just the right balance in your diet. Depending on factors like your genetics, age, health problems, eating and drinking habits, exposure to environmental toxins, and stress, people respond very differently to the exact same food—even if it’s supposedly “good for you.”
One person can have a piece of pizza with a mild increase in their blood glucose level while for others it causes a major spike. Certain foods such as candy, soda pop, fruit juice, white breads and crackers are obvious blood sugar spikers. However, sometimes seemingly healthier foods can cause great variation in glucose levels.
One Size Does Not Fit All
Unfortunately, most conventional doctors usually aren’t as attuned to those differences between their patients, and so they end up practicing what I would consider bad medicine—a “one-size-fits-all” approach that doesn’t seem to fit anybody. The concept of individuality in nutrition and medicine explains a lot of the contradictory findings of many studies, such as when only half of the subjects benefited from a certain supplement (or drug, as the case might be). Holistic doctors like myself, of course, understand that there’s a huge range of genetics and lifestyles among people—and that studies of only a few hundred of them can’t account for all these genetic variations (which to some degree we can test for genetic variations known as single nucleotide polymorphisms (SNP’s). That’s why we personalize pretty much every treatment and therapy based on each individual patient’s needs. And there’s solid science to support this “custom fit” approach to medicine—because research shows how individualized nutrition could help people prevent and fight disease. And it’s nothing short of amazing. What’s your carbohydrate sensitivity?
A team of researchers at the Weizman Institute of Science in Israel have zeroed in on how factors like genetics, lifestyle, insulin sensitivity, and gut microbe composition can influence your response to carbs. And it turns out that it can vary wildly from person to person! If there were a way to predict what those responses would be ahead of time, then we could map out everyone’s unique path to blood sugar control and disease prevention. Well, that dream may be closer than ever to becoming a reality. For the study, 800 subjects aged 18 to 70 years old were fed one of four types of standardized breakfast meals over the course of a week. Each planned meal contained 50 grams of carbohydrate, while the subjects ate their usual meals and went about their usual daily activities the rest of the time. In the end, after a total of 46,898 meals, it became very clear that not everybody responds the same way to the same food… and that a food’s glycemic index can’t predict with certainty how it will affect a person’s blood sugar levels.
In the study, some people were prone to react strongly to specific types of carbohydrate (“carbohydrate sensitive”), and others didn’t really react at all to the same exact type of carb (“carbohydrate insensitive”). And although the individual participants differed from each other in how they responded to carbohydrates and other foods, those individuals were consistent in their own responses. For example, some people consistently had a modest 15 mg/dl increase in blood sugar after eating bread, while others consistently had a 79 mg/dl jump (which, to me, would indicate prediabetes). You could almost say that each person had their own glycemic index—and that makes the food’s ranking on the glycemic index less helpful. While these results may seem unexpected, given what we’ve been told about how foods are supposed to affect all our bodies, they bring us one step closer to understanding how to change our expectations to reflect more accurately what’s happening in the body. And what we do with that information is what’s exciting about this study.
With all the information about carbohydrate sensitivity collected, the researchers developed a computer program to predict how much one person’s blood sugar would rise after eating a certain food. They then used the program to create personalized meals that would be designed to control the participants’ blood sugar—and their initial accuracy was impressive at 70 percent. With a few more tweaks, it would probably be accurate for 90 percent of people—which is far better than any dietician or blanket diet recommendations could do. The focus on blood sugar in this study is important, since glycemic problems can lead to many other conditions—like prediabetes, obesity, and type 2 diabetes—and increase the risk of inflammatory disorders, heart disease, cancer, and any other diseases.
Gut microbiome and blood sugar balance
The Israeli researchers also wanted to understand how blood sugar levels could differ so much between the subjects of their study, so they looked at each of their gut bacteria (or “microbiome”). Now, we know that the “good” and “bad” bugs in our gut can be diverse—and it turns out that which bugs you have (and how many of them) has a huge influence over your responses to what you eat. Specifically, they found that certain types of microbes were associated with blood sugar levels. Likewise, other bacterial species are associated with blood sugar spikes, as well as obesity.
What Foods Work Best for You?
We help patients fast-track their sensitivity to foods and blood sugar swings through a few methods. This includes blood food sensitivity testing, continuous blood glucose monitoring (i.e. Free Style Libre or Dex Com), and diet diaries.
Of course, it is important to eat foods rich in prebiotics and probiotics for a healthy gut flora, which are involved in glucose metabolism.
Zeevi D, Korem T, Zmora N et al. Personalized Nutrition by Prediction of Glycemic Responses. Cell. 2015;163(5):1079-1094. doi:10.1016/j.cell.2015.11.001
Dr. Mark Stengler is a leading Naturopathic Medical Doctor and author. He practices with his wife Dr. Angela Stengler, at the Stengler Center For Integrative Medicine in Encinitas, California (855-DOC-MARK).