Pistachios can be consumed as a portion-controlled snack for individuals restricting calories to lose weight without concern that pistachios will cause weight gain. By comparison to refined carbohydrate snacks such as pretzels, pistachios may have beneficial effects on triglycerides as well.

There is a widely held view that nut consumption due to its high fat content leads to weight gain and unhealthy lipid profiles. In order to study the effects of pistachio snack consumption in obese subjects under real world conditions, subjects were randomly assigned to two weight reduction diets with a 500 Cal deficit diet based on RMR using whole foods and including an afternoon snack of 3 ounces (240 Cal) of pistachios (PS, n = 27) or two ounces of pretzels (PR, n=26) (220 Cal) over 12 weeks. Both groups lost weight during the 12 week study (time trend p<0.001) and there were no differences in weight loss between the pretzel and pistachio groups (PS 189.6 ± 5.2 to 181.0 ± 6.2 vs. PR 189.8 ± 4.0 to 182.5 ± 4.4 lb). At 6 weeks, triglycerides were significantly higher in the PR group compared to the PS group (132 ± 18 mg/dl vs. 90 ± 9 mg/dl, p< 0.04) and a time trend difference was noted between the two groups over the 12 weeks (p<0.01). There were no significant differences in body fat, lean body mass, cholesterol, HDL, insulin, glucose or blood pressure between the groups. Therefore, by comparison to refined carbohydrates, pistachios may have beneficial effects on blood lipids. Despite claims that energy‐dense foods promote weight gain, pistachios can be consumed as a snack to enhance diet quality and palatability by individuals following a weight loss diet without fear that the ingestion of 3 ounces of pistachios per day will impair weight loss.