The Research:
Many randomized controlled studies have been conducted and funded by the Almond Board of California to examine the consumption of almonds in relation to blood glucose control. Studies suggest that including almonds in a healthy diet may have benefits for people with type-2 diabetes (T2D) as well as for those with prediabetes, who are at risk for developing T2D.
One recent studyii conducted in India showed that almonds had a positive impact on both blood sugar control and markers of heart health in adults with type-2 diabetes (T2D). Fifty Asian Indian adults with T2D and elevated cholesterol levels substituted 20% of their daily calories with whole, unroasted almonds as part of a well-balanced diet. They not only saw improvements in hemoglobin A1c (an indicator of longer-term blood sugar control), but in several cardiovascular risk factors linked to type 2 diabetes, including:
- Waist circumference: an indicator of health risk associated with excess fat around the waist
- Waist-to-height ratio: a measure of body fat distribution
- Total cholesterol: a measure of the amount of cholesterol in the blood
- Triglycerides: a form of fat in the blood that can raise risk for heart disease
- LDL-cholesterol: the harmful type of cholesterol that is a main source of cholesterol buildup and blockage in the arteries
- C-reactive protein: a marker of inflammation in the body
A randomized trial2 in 19 U.S. adults (including seven with T2D) reported a 30% reduction in postprandial glycemia in participants with T2D after eating a a test meal containing one ounce (28 grams) of almonds compared to an almond-free test meal similar in calories, fat and available carbohydrate. The same researchers looked at the longer-term effects of almonds on glucose control in a small group of 13 adults with T2D. Participants consumed a daily one-ounce serving of almonds (five days per week for 12 weeks) or a cheese snack with the same number of calories. After 12 weeks, hemoglobin A1c in individuals with T2D was reduced by 4% from baseline in those in the almond group. The small study size is a limitation of this study. Larger studies will be useful in better understanding the impact of almonds on blood glucose in people with T2D.
Another 12-week study3 assessed the impact of almond consumption (~two ounces or 60g/day) in a cholesterol-lowering diet on short- and long-term glycemic control, blood lipids, endothelial function, oxidative stress and inflammation in 33 Chinese (Taiwanese) adults with T2D. Results showed that among patients with better-controlled blood glucose levels (baseline HbA1c ≤8%), the diet with almonds reduced HbA1c by 3% and fasting blood sugar levels by 5.9% compared to the control diet, suggesting that including almonds in a healthy diet might help further improve blood sugar control in T2D patients with HbA1c ≤8%. Serum cholesterol levels and biomarkers for inflammation and oxidative stress remained unchanged over the course of the study. As with the previous study, the relatively small sample size is a limitation, so larger studies will be useful in better understanding the impact of almonds on blood glucose in people with T2D.
Studies also suggest that as part of a health diet, almonds may have benefits for people with prediabetes.