Two Apples a Day May Lower Cholesterol
There is a saying that "an apple a day keeps the doctor away". It may be the time to update this to "two apples a day keeps the doctors away".
Koutsos et al. conducted a randomized, controlled, crossover, intervention study. Healthy mildly hypercholesterolemic volunteers (n=40, 23 women, 17 men), with Body Mass Index (BMI) 25.3 ± 3.7 kg/m2 and age 51 ± 11 years (mean ± standard deviation), consumed 2 apples/day (Renetta Canada, rich in proanthocyanidins) or sugar- and energy-matched apple control beverage for 8 weeks for each intervention, separated by a 4-week washout period.
The daily dose of two apples was 340 gram, which provided 990 mg polyphenols, 854 mg proanthocyanidins, and 8.5 g total fiber (3.7 g soluble) compared with 2.5 mg polyphenols, 1 mg proanthocyanidins, and <0.5 g total fiber from the daily intake of 500 mL sugar-matched control beverage.
Compared with control beverage (CB), whole apple (WA) ingestion decreased serum total (WA: 5.89 mmol/L; CB: 6.11 mmol/L; P = 0.006) and LDL cholesterol (WA: 3.72 mmol/L; CB: 3.86 mmol/L; P = 0.031), triglycerides (WA: 1.17 mmol/L; CB: 1.30 mmol/L; P = 0.021), and intercellular cell adhesion molecule-1 (WA: 153.9 ng/mL; CB: 159.4 ng/mL; P = 0.028). The response to endothelium-dependent microvascular vasodilation was greater after eating the whole apples [WA: 853 perfusion units (PU), CB: 760 PU; P = 0.037] than after the control beverage. Apples had no effect on blood pressure or other cardiovascular markers.
This study showed that when people with slightly high cholesterol ate two large apples a day for eight weeks, it lowered their levels of cholesterol and triglycerides, and enhanced beneficial vascular effects. These changes may be small but can be significant if kept long term, which could reduce the risk of a stroke or heart attack.
References:
Koutsos, A., Riccadonna, S., Ulaszewska, M. M., Franceschi, P., Trošt, K., Galvin, A., Braune, T., Fava, T., Perenzoni, D., Mattivi, F., Tuohy, K. M., Lovegrove, J. A. (2019). Two apples a day lower serum cholesterol and improve cardiometabolic biomarkers in mildly hypercholesterolemic adults: a randomized, controlled, crossover trial. The American Journal of Clinical Nutrition. doi:10.1093/ajcn/nqz282