Eating a lot of cashews every day for two months might raise blood sugar levels in people with metabolic syndrome, even though longer-term sugar markers don’t change — so cashews could be affecting blood sugar in the short run.

What we've found so far suggests that eating cashews daily might increase fasting blood sugar in adults with metabolic syndrome over the short term. Our analysis of the available evidence shows this effect was observed over a two-month period, even though longer-term blood sugar markers did not change [1]. We looked at one key assertion from the data, which is supported by 48.0 studies, with no studies refuting it. According to this assertion, daily cashew consumption may lead to higher fasting blood sugar levels in people with metabolic syndrome after several weeks [1]. This means that in the short run—specifically within two months—blood sugar measured after fasting could go up. However, the evidence does not show changes in longer-term markers of blood sugar control, which suggests the body may be adapting or that the effect is limited to immediate fasting levels. Our current analysis does not explain why this short-term rise occurs. It also does not tell us whether this effect continues beyond two months or what it means for overall health in the long run. Since all the supporting evidence points in one direction and none contradict it, the data we’ve reviewed leans toward a short-term increase in fasting blood sugar with daily cashew intake in this population. Still, we emphasize that this is a narrow body of evidence—only one assertion analyzed, even if backed by many studies. We cannot say for sure how strong or meaningful this effect is in daily life, or whether it outweighs any other benefits cashews might have. Practical takeaway: If you have metabolic syndrome and eat cashews every day, you may want to monitor your fasting blood sugar, especially over the first couple of months. The evidence we’ve reviewed hints at a possible short-term rise, but more analysis is needed to understand the full picture.