Effects of chronic peanut consumption on energy balance and hedonics

Abstract

OBJECTIVE:To investigate the effects of chronic peanut consumption on energy balance and hedonics. DESIGN: Thirty-week, cross-over, intervention study. Participants were provided 2113 AE 494 kJ=day (505 AE 118 kcal=day) as peanuts for 8 weeks with no dietary guidance (free feeding -FF), 3 weeks with instructions to add peanuts to their customary diet (addition -ADD) and 8 weeks where peanuts replaced an equal amount of other fats in the diet (substitution -SUB). SUBJECTS: Fifteen, healthy, normal-weight (BMI of 23.3 AE 1.8) adults, aged 33 AE 9 y. MEASUREMENTS: Dietary intake, appetitive indices, energy expenditure, body weight and hedonics. RESULTS: During FF, peanut consumption elicited a strong compensatory dietary response (ie subjects compensated for 66% of the energy provided by the nuts) and body weight gain (1.0 kg) was significantly lower than predicted (3.6 kg; P < 0.01). When customary dietary fat was replaced with the energy from peanuts, energy intake, as well as body weight, were maintained precisely. Participants were unaware that body weight was a research focus. Resting energy expenditure was increased by 11% after regular peanut consumption for 19 weeks (P < 0.01). Chronic consumption of peanuts did not lead to a decline in pleasantness or hunger ratings for peanuts nor did it lead to any hedonic shift for selected snack foods with other taste qualities during any of the three treatments. CONCLUSIONS: Despite being energy dense, peanuts have a high satiety value and chronic ingestion evokes strong dietary compensation and little change in energy balance.

Effects of peanut oil consumption on appetite and food choice

“…In another study, incorporation of peanuts into the habitual diets of free-living subjects for 8 weeks led to markedly lower Effects of peanut oil consumption SS Iyer et al than predicted weight gain. 8 This was attributed to a combination of high-satiety value and inefficient use of energy from peanuts. In another arm of the same study, addition of peanuts to the customary diet prompted comments about the high-satiety value of the nuts.…”

“…This level of compensation is lower than previously reported with whole peanuts and tree nuts. 8 This suggests that while the fat content contributes to compensation, other factors are also involved. The non-fat fraction of peanuts may potentiate their satiety inducing effects.…”

“…In the Nurses Health Study, women who rarely consumed nuts had a BMI of 24.8 kg/m 2 compared to 23.4 kg/m 2 for women consuming nuts more than five times per week. Intervention trials [5][6][7][8][9] provide additional support for an inverse relationship between nut consumption and both lipid profiles and BMI. In 2003, the Food and Drug Administration approved a qualified health claim for nuts stating that 'Scientific evidence suggests, but does not prove that eating 1.5 ounces of most nuts per day as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease'.…”

“…11 While inclusion of nuts in an energy-controlled diet reportedly does not compromise weight loss, the influence of nut consumption on body weight in free-living, nondieting individuals is less well studied. In a recent intervention, 8 participants were provided 500 (7136) kcals of whole peanuts with no dietary guidance for 8 weeks. Nonsignificant changes in body weight were observed due, in part, to dietary compensation for 66% of the energy from the peanuts.…”

“…Peanuts are rich in protein (26% by weight) and dietary fiber (8.5%) and these components hold satiety effects that may moderate intake. 8 The largest energy component of peanuts is their lipid fraction (49%) which is predominantly (40%) unsaturated fat. Evidence both from human and animal studies suggest that mono and polyunsaturated fatty acids are more readily oxidized than saturated fats and may be more satiating.…”