Daily Strawberry Consumption Tied to Improved Insulin Resistance, Study Finds

Although overall consumption of fruits and vegetables is declining in the U.S., strawberries are still among the top five favorites for Americans. But consuming this bright red fruit on a regular basis may be more beneficial than just increasing your fruit and vegetable intake.

Aside from being rich in vitamins and nutrients, new research suggests that regularly consuming strawberries also may improve insulin resistance. In fact, according to a study published in Nutrients, strawberry consumption decreased inflammation, insulin resistance, and the density of lipid particles in the blood.

About the Study

Thirty-three adults who met the criteria of presenting with at least one feature of metabolic syndrome—such as having obesity, abdominal adiposity based on waist circumference, or elevated LDL cholesterol levels—participated in a randomized controlled crossover study over the course of 14 weeks.

Participants were assigned to either a control group, low-dose strawberry group (the equivalent of one serving), or high-dose strawberry group (the equivalent of 2 1/2 servings). Those in the strawberry groups ingested freeze-dried strawberry powder as a beverage. Participants were seen on a bi-weekly basis by a registered dietitian to submit food logs. Compliance with the protocol was based on the return of any unused strawberry powder.

The study found a significant reduction in both serum insulin and serum resistance with the high-dose strawberry protocol. The same protocol also elicited a borderline significant difference in lowering LDL cholesterol levels.

"Strawberries are full of essential nutrients—fiber, folate, vitamin c, and manganese," says registered dietitian Carrie Moody, RD. "While you may have heard to avoid fruit because it contains carbs or it can spike your blood sugar levels, strawberries have a low glycemic index."

What The Experts Say

Strawberries are rich in polyphenol, a compound found in plants as well as anthocyanin, which numerous studies suggest plays a role in the prevention of chronic disease. Strawberries also boast a low glycemic index and are relatively low in sugar. For those with diabetes or who are interested in weight management, including a 2 1/2 cup serving of strawberries may be especially beneficial.

"Strawberries are very nutritious and a favorite among many, particularly those who are looking to lose weight," says Diana Rodriguez, MS, RD, CDN based in New York City. "Strawberries are low-calorie, and 2 1/2 cups of strawberries contain about 7.5 grams of fiber, specifically soluble fiber. Soluble fiber helps absorb water and forms a gel-like substance in the digestive system, slowing down the stomach’s emptying, thus increasing the feeling of fullness while helping regulate appetite." 

Additionally, Rodriguez notes that studies suggest that consuming a higher amount of fruit could be associated with a lower risk of weight gain over time. If the idea of scarfing down two and a half cups of strawberries in one sitting seems a bit much, keep in mind that the berries used in the study were freeze-dried.

And because all forms of produce count toward your daily goal, this is a great option that is readily available year-round to those who find it more appealing. You can include them as part of an overall balanced snack, as a topping for yogurt alongside nuts, or even blended into a smoothie. Still, it is important to consider balance—no matter how nutrient-dense food is—says registered dietitian Carrie Moody, RDN.

"Strawberries are a great fruit option that will not significantly raise your blood sugar levels," says Moody. "It’s always a good idea to pair strawberries with a source of protein [or] a healthy fat to further curb a spike in blood sugar."

Although a difference in glucose and conventional lipid profiles did not change in any arm of the study, the strawberries lowered insulin resistance, improved lipid particle profiles, and decreased levels of an inflammation biomarker in the blood.

"Strawberries are a great snack option that can quickly satisfy your sweet tooth and help support weight loss," advises Rodriguez.