Precision Slicing

On the Hunt for Precision Personalized Diets

Precision nutrition is a concept with an almost irresistible allure. It borrows on the cachet of precision medicine. On top of that, frustration with the presently imprecise nature of nutrition science makes the promise of precision personalized diets especially appealing. So in pursuit of this idea, a new study in Nutrients offers some tantalizing clues.

Clear Patterns in the POUNDS LOST Study

Researchers led by Mads Hjorth tapped into the rich data of the POUNDS lost study. They looked at a markers of glucose metabolism to predict which people would lose the most weight on which diet – high fat, low fat, or high fiber. And they found some pretty clear patterns.

After two years, people with high insulin resistance lost the most weight on a high fat, high protein diet. Meanwhile, people with normal blood glucose lost the most weight on a low fat, high protein diet. And finally, people with prediabetes and low fasting insulin levels seemed to get the most benefit from extra fiber in their diets.

Do Macronutrients Matter?

When researchers published the primary results of the POUNDS LOST study in the New England Journal of Medicine, the headlines were clear. In the contest between low fat and low carb diets, there is no clear winner. This is a finding researchers reaffirm repeatedly. Diana Thomas summed it up for us:

Macronutrients may be a distraction. Very often it all boils down to adherence. What’s a healthy pattern of eating that a person can follow for the long term?

Yet again, these new results tempt us to take a hard look at that conclusion. Maybe there’s not one right answer for everyone. Can we find the right diet for the right person?

Maybe. But remember, these new results by Hjorth et al come from a post hoc analysis – not a real experiment. As the authors say:

These different dietary patterns still need to be compared in randomized trials where the adherence in real-life settings (behavioral support and cultural and social factors) should be removed to investigate the effect of the individual underlying biology.

A Road Well-Traveled

We’ve been down this road before. In the DIETFITS study, Christopher Gardner and colleagues tested the proposition that insulin secretion might point to the right diet for the right person for weight loss. But no, it did not.

Thus, the search for precision personalized diets continues. You can buy a DNAFit report or  a Nutrisystem DNA Body Blueprint. People are even hyping a personalized artificial intelligence diet. Make no mistake though, this science is far from complete. Definitive answers may come, but they’re not here yet.

So if you really want a precision personalized diet, your best bet for now is to see a registered dietitian.

Click here for the study by Hjorth et al and here for more on the questo for personalized diets.

Precision Slicing, photograph © / flickr

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March 13, 2019

2 Responses to “On the Hunt for Precision Personalized Diets”

  1. March 13, 2019 at 11:11 am, Mary-Jo said:

    Dietitians love working with each person, spending time finding their likes and dislikes, trying to honour their food and diet history, and just helping people shop, cook, and eat the food they enjoy, can afford, and which makes them feel and look great. As an RDN who has worked with people who need to have as precise as possible food and nutrition match their bodies’ disease conditions (people with inborn errors of metabolism, heart disease, renal failure, cystic fibrosis, celiac, food allergies, etc.), I have seen, first hand, how the right foods/nutrients and amounts truly changes lives! With obesity, it is very helpful when time, effort, and resources are offered to people to elucidate what’s going on with their body and multi factorily and to individualized the diet, nutrients, and treatment plan that works best for them.

  2. March 20, 2019 at 3:36 am, Mary said:

    How well does any diet do after 3 -5 years? Please check in with us and report those results. The evidence shows most will regain all and some more weigh than they lost.

    Health behaviors such a physical activity, consuming whole foods, community connections and others can provide sustainable health benefits without weight loss… and ultimate regain.