Study Says Walnuts Can Reduce Diabetes Risk By Half, But Results Aren’t All They’re Cracked Up To Be

When we saw the headline that a new study found that consuming walnuts can cut risk for type 2 diabetes in half, we were excited. Enjoy a crunchy snack while protecting our health? That sounds wonderful.

The study, published in the online journal Diabetes Metabolism/Research and Reviews, and conducted at the University of California Los Angeles, found that people who ate walnuts had a 47 percent lower risk of developing type 2 diabetes as compared to those who didn’t eat nuts. Women who ate walnuts experienced even greater benefits from walnut consumption.

But the results may not be all they’re cracked up to be.

Photo: pixabay/Ajale
Photo: pixabay/Ajale

The critique

Some news outlets shared the walnut claims that likely health-nuts and walnut-lovers alike. But NHS Choices (the website for the National Health Service in the United Kingdom) released an article a few weeks after the research came out titled, “No proof walnuts prevent diabetes.” The article says that, “Overall this study does not provide good evidence that diabetes can be prevented by eating walnuts.”

NHS claims that the American study wasn’t nearly thorough enough to make definite conclusions. Oh, and the study was funded in part by the California Walnut Association. Which, while suspect, is not enough in itself to discount the study. But the NHS website also cites these reasons to take the new claims with a grain of salt:

  • The study, which looked at survey data from 1999 to 2014 only looked at people’s diets at one point in time, specifically a 24-hour period based on participant recall.
  • The results don’t adjust for other health and lifestyle factors. If people who eat walnuts also have healthier diets overall, then the reduced risk may or may not be affected by walnuts specifically.
  • The research was cross-sectional, which means it used data from already existing surveys. This type of study can show correlation, but not cause and effect.

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The good news about walnuts

No need to worry, walnut-fans, there is plenty of research to show that walnuts are a healthy choice, if not a miracle-nut. The American Diabetes Association says that a handful of walnuts every day can improve diet quality and reduce some diabetes risk factors. Specifically, LDL cholesterol (the unhealthy type of cholesterol) can be reduced with regular walnut-consumption.

These results were based on a more trustworthy study published in BMJ Open Diabetes Research and Care and conducted at Yale University Prevention Research Center. That study found that consistent walnut consumption (daily for six months), improved overall diet quality, which results in lower risk for chronic disease. Walnut consumption also improved heart and blood vessel function.

Photo: AdobeStock/hakase420
Photo: AdobeStock/hakase420

More Nut News

Walnuts have been praised for their omega-3 fatty acid content (the healthy fats) and those fats and their high protein content help you get and stay full. And though they are energy-rich, they Yale study found that they were not associated with weight gain.

Walnuts are a good source of fiber, vitamin E, potassium, and antioxidants. Add them to oatmeal, yogurt, salmon, or snack on them plain. But fair warning: candied walnuts do not count as a health food!

Photo: AdobeStock/dimasobko
Photo: AdobeStock/dimasobko

So what now?

The latest walnut claims are another example of the “If it sounds too good to be true” principle. What’s frustrating is that walnuts are indeed a healthy choice, but making leaps and bounds about what they can do is misleading to folks who are doing their best to eat healthy. Worse, people may give up on eating healthy if they learn not to trust nutrition recommendations.

The best source of nutritional advice is a doctor, nutritionist, or registered dietitian. Research suspect claims by checking out sources you trust, and remember that nutritional advice is slower to change than many media sources would have you think. Simple guidelines have so far stood the test of time: focus on fresh fruits and vegetables and limit sugary and processed foods. Stay healthy, friends!

Photo: pixabay/Varhols
Photo: pixabay/Varhols
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