Benefits
Blood cholesterol in adults with excess weight
In 27 adults with metabolic syndrome, 50 g/day of freeze-dried strawberry for 8 weeks lowered total and LDL cholesterol versus a water control. In 60 adults with abdominal adiposity, only the 50 g dose beat its matched control over 12 weeks; 25 g did not. A 4-week crossover in 34 adults found no LDL change, and most trials saw no change in blood pressure.
Insulin and blood sugar markers over 6 to 12 weeks
In a 28-week crossover in 25 adults with prediabetes, 12 weeks of 32 g/day of freeze-dried strawberry lowered insulin, insulin resistance, fasting glucose and HbA1c versus a no-strawberry period in adjusted models. In 36 adults with type 2 diabetes, 50 g/day for 6 weeks lowered HbA1c versus placebo, with no change in fasting glucose. Other trials saw no glucose change.
After-meal insulin and inflammation markers
In a crossover trial in 24 overweight adults, a drink with 10 g of freeze-dried strawberry taken with a high-carbohydrate meal lowered the after-meal rise in insulin, high-sensitivity CRP and IL-6 compared with a matched placebo drink. Glucose, TNF-alpha and IL-1 beta did not differ. Over 3 to 12 weeks, several other trials found no change in CRP, while a 12-week prediabetes trial reported lower hsCRP and IL-6.
Lipid peroxidation and antioxidant status markers
Both 25 and 50 g/day lowered blood malondialdehyde, a lipid peroxidation marker, versus matched controls over 12 weeks, and 50 g/day raised total antioxidant status versus placebo in adults with type 2 diabetes. A crossover in older adults saw antioxidant capacity rise on strawberry and fall on control. A 3-week crossover in obese adults found no difference in antioxidant status.
Memory and processing speed in older adults
In 37 healthy adults aged 60 to 75, 24 g/day of freeze-dried strawberry for 90 days improved word recognition and a virtual navigation task versus placebo, while most other tests, gait and balance did not change. In a crossover in 35 older adults, 26 g/day improved processing speed, but episodic memory improved during the control phase instead.
Knee comfort scores in adults with excess weight
In a 26-week crossover in 17 adults with obesity and knee osteoarthritis, 50 g/day of freeze-dried strawberry for 12 weeks lowered constant, intermittent and total knee pain scores on one questionnaire, a disability score, and IL-6, IL-1 beta and MMP-3 versus a matched control. A visual pain scale and CRP did not differ.
Source of vitamin C, pelargonidin-3-glucoside and ellagitannins
USDA lists 32 kcal, 2.0 g of fiber, 58.8 mg of vitamin C and 24 mcg of folate per 100 g of raw strawberries. Pelargonidin-3-glucoside is the main anthocyanin, and the berries also carry ellagitannins that gut bacteria turn into urolithins. This is a composition note, not a measured health effect.
Mechanism of action
Pelargonidin-3-glucoside is absorbed and conjugated
After 100, 200 or 400 g of strawberry puree, pelargonidin-3-glucoside and three pelargonidin glucuronides appeared in urine in amounts that rose in step with the dose, so absorption was not saturated at these intakes. With a strawberry drink, plasma pelargonidin-3-glucoside and pelargonidin sulfate rose after a meal.
Ellagitannins become urolithins in the gut
Strawberry ellagitannins are converted by gut bacteria to urolithins, which are excreted in urine as glucuronides. In 20 volunteers, fresh berries and a heat-processed puree gave similar urolithin output; all produced urolithin A but only 3 produced urolithin B, and output varied widely between people.
Short-term artery widening linked to phenolic metabolites
In a crossover trial, flow-mediated dilation, a measure of how well an artery widens, was higher 1 hour after a 50 g strawberry drink than after a control drink, and one microbial phenolic metabolite correlated with the change. After 4 weeks of daily intake, fasting flow-mediated dilation did not differ from control.
Clinical trials
Randomized controlled trial of 4 cups a day of a drink made from 50 g of freeze-dried strawberries (about 3 cups fresh) versus the same volume of water, which was not matched for calories or fiber; the California Strawberry Commission donated the powder and the work was supported in part by an NIH-funded General Clinical Research Center grant at the University of Oklahoma Health Sciences Center and by Oklahoma State University. (Basu et al. 2010, Nutr Res)
27 adults with metabolic syndrome (25 women, 2 men; mean age 47, mean BMI 37.5).
Versus control at 8 weeks, total cholesterol fell from 5.8 to 5.2 mmol/L and LDL cholesterol from 3.5 to 3.1 mmol/L, and small LDL particles and the adhesion molecule VCAM-1 also fell (all P < .05). Glucose, triglycerides, HDL cholesterol, blood pressure and waist circumference did not change.
Randomized dose-response controlled trial with four drinks: 25 g/day or 50 g/day of freeze-dried strawberry, each with its own control drink matched for calories and fiber; supported by a California Strawberry Commission grant, Oklahoma State University and the NIH. (Basu et al. 2014, J Nutr)
60 adults with abdominal adiposity and raised blood lipids (55 women, 5 men; mean age 49, mean BMI 36).
Only the 50 g dose lowered total and LDL cholesterol versus its control; the 25 g dose did not. Both doses lowered serum malondialdehyde versus controls (P < 0.05). Adiposity, blood pressure, glycemia, HDL cholesterol, triglycerides, CRP and adhesion molecules did not change.
Double-blind, randomized crossover feeding study with all meals provided: 3 weeks of strawberry powder (equal to four servings of frozen strawberries a day) and 3 weeks of a strawberry-flavored control; funded by the USDA and a California Strawberry Commission grant, the Commission supplied the powder, and the first author sat on its scientific advisory committee. (Zunino et al. 2012, Br J Nutr)
20 healthy adults aged 20 to 50 with obesity (BMI 30 to 40; 13 women, 7 men).
Total cholesterol was about 4% lower with strawberry than control, but because of a carry-over effect this was tested with first-period data only (10 per group) and a one-tailed test. Fibrinogen was slightly higher with strawberry than control, though within the normal range; LDL cholesterol, the other inflammatory markers, antioxidant status (ORAC, TAS, 8-isoprostane) and blood pressure did not differ between treatments.
Randomized, double-blind controlled trial of 2 cups a day of a drink with 50 g of freeze-dried strawberry (about 500 g fresh) versus a macronutrient-matched strawberry-flavored placebo powder; the abstract does not state the funding source. (Moazen et al. 2013, Ann Nutr Metab)
36 adults with type 2 diabetes in Iran (23 women; mean age 52, mean BMI 27.9).
Versus placebo, HbA1c fell (the abstract calls it a decreasing trend of 5.7%, P < 0.05) and total antioxidant status rose (P < 0.01). CRP and malondialdehyde fell from baseline within the strawberry group, a within-group change. Fasting glucose and body measurements did not change.
Randomized crossover meal study: a high-carbohydrate, moderate-fat meal with a milk-based drink containing 10 g of freeze-dried strawberry (about 100 g fresh) or a placebo drink matched for flavor, energy and nutrients, with blood followed for 6 hours; funded by a California Strawberry Commission grant. (Edirisinghe et al. 2011, Br J Nutr)
24 overweight adults (10 men, 14 women) analyzed; 26 recruited.
Plasma pelargonidin-3-glucoside and pelargonidin sulfate rose with strawberry (P < 0.001). The after-meal rise in high-sensitivity CRP and IL-6 and the insulin response were lower with strawberry than placebo (P < 0.05). Glucose, TNF-alpha, IL-1 beta and PAI-1 did not differ between drinks.
Randomized, double-blind, placebo-controlled parallel trial of 24 g/day of freeze-dried strawberry (about 2 cups fresh) or a placebo powder; funded by the USDA and the California Strawberry Commission, which supplied both powders. (Miller et al. 2021, Br J Nutr)
37 healthy adults aged 60 to 75 (22 men, 15 women) in the per-protocol analysis; the paper reports 54 enrolled and 16 who did not complete.
Versus placebo across visits, the strawberry group had shorter latencies on a virtual spatial navigation task (P = 0.020) and higher word recognition on the California Verbal Learning Test (P = 0.014). Other recall measures, attention, task switching, trail making, digit span, mood, gait and balance did not differ.
Randomized, double-blind crossover trial of a drink with 50 g/day of freeze-dried strawberry or a control powder matched for calories and fiber, each for 12 weeks with a 2-week washout; the California Strawberry Commission provided both powders, with university and NIH support. (Schell et al. 2017, Nutrients)
17 adults with obesity (mean BMI 39) and x-ray evidence of knee osteoarthritis; mean age 57.
Versus control, constant, intermittent and total pain on the ICOAP questionnaire, the HAQ-DI disability score, and serum IL-6, IL-1 beta and MMP-3 were lower (all p < 0.05). The visual analog pain scale, CRP, nitrite, glucose and lipids did not differ.
Randomized, single-blinded controlled crossover trial of 32 g/day of freeze-dried strawberry (about 2.5 servings fresh) or no strawberries, 12 weeks per period, with glycemic control as the primary outcome; PubMed lists NIH and non-government support. (Basu et al. 2025, J Nutr)
Adults with prediabetes; 25 recruited in each period.
In models adjusted for age, sex, BMI, calories, activity and baseline values, the strawberry period lowered serum insulin, insulin resistance, fasting glucose, HbA1c and total cholesterol, and also body weight, high-sensitivity CRP and IL-6, versus control (all P < 0.05). The control period used no placebo powder.