Nutritional Pearls: Eat Your Vegetables, Reduce Your Risk of Diabetes

Mark is a 35-year-old man who is concerned about his risk of developing diabetes. When asked about his diet, he tells you that although he tries to eat at least one piece of fruit a day, he often does not have any vegetables.

How would you advise your patient?
 

(Answer and discussion on next page)

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Mom said, "Eat your vegetables."

What she didn't say (and probably didn't know at the time) was, "eat your vegetables or risk developing diabetes."

I know from talking to my patients that most Americans aren't eating the recommended amount of fruits and vegetables, which in the US is 640-800 grams/day (about 22.5 to 28 ounces or between 6.5 and 8 servings).

In Sweden, the recommended intake of fruits and vegetables is lower, with the minimum recommended intake an average of 500 grams/day, or 17.6 ounces (that's about 5 servings at 3.5 ounces each). According to a team of researchers in Sweden, on average, the Swiss consume only about 126 g per day of fruits and berries and only about 175.5 g per day of vegetables (that includes legumes but does not include potatoes).

The Research

The authors of today's article surveyed over 35,000 adults in Stockholm County, via online or mail-in questionnaire, first in 2010 and then again in 2014

The over 35,000 men and women were between the ages of 18 and 84 years, free from certain chronic conditions at the start of the study, and responded fully to both surveys, which gathered not only demographic and health information and history but also customary dietary intake.

Initially, the authors had planned to break out the intake of fruits and vegetables separately into 3 increasing levels of intake each but found that the participants ate so little fruits and vegetables that the best they could do was to break up the participants into those who consumed less than 2 servings per day versus those who consumed more than 2 servings per day. Indeed, the authors note that "Almost three-quarters of the respondents consumed fewer than 2 servings of vegetables per [day]."

The Results

The fruit and vegetable consumption of those who reported developing type 2 diabetes in the 2014 survey was then compared to the fruit and vegetable consumption of those who did not, taking into account gender, body mass index, education, smoking status, and a number of other common variables.

While the authors could find no statistically significant relationship between fruit intake and diabetes risk, for men only they found that those who consumed less than 2 servings of vegetables per day were 162% more likely to develop diabetes than those who consumed 2 or more servings per day. Remember, this measure did not include potatoes, although they are indeed technically vegetables.

It's worth noting that that about 2/3 of male participants consumed less than 2 servings per day of vegetables, while the same was true for only 1/3 of female participants, which may explain why the results were applicable to men and not women.

What’s the Take Home?

In this study, consuming a minimum of 2 servings of vegetables a day made a huge difference in risk of diabetes, at least for men. That's not 2 more servings than you're consuming now, that's just two servings, period. Make sure you're getting your vegetables (and fruits) by piling your sandwich high with veggies like sprouts, lettuce, tomatoes, and peppers, and make sure to have a vegetable that's not a potato on the side at dinner.

Reference:

Ahmed A, Lager A, Fredlund P, Elinder LS. Consumption of fruit and vegetables and the risk of type 2 diabetes: a 4-year longitudinal study among Swedish adults. J Nutr Sci. 2020. 9(e14) doi:10.1017/jns.2020.7