Cardiovascular Effects of Purple-Fleshed Potatoes

This study is being done to evaluate the effect on cardiovascular biomarkers and anthocyanin-derived plasma metabolites of Peruvian native purple-fleshed potato consumed over a 4-week period by prehypertensive men ages 18-40 years old. Subjects will undergo blood pressure monitoring, anthropometric measurements, laboratory analysis, plasma metabolic profile assessments and microbiome metagenomic analysis before and after finishing the potato consumption period.

Hypertension is a chronic disease that affects over 20% of Peruvians aged 15+, with higher prevalence in men. Previous studies on purple flesh varieties have shown reductions in blood pressure and improvements in vascular function. Potatoes are a major dietary staple and a source of many compounds beyond carbohydrates, including vitamins, minerals, and polyphenols. Anthocyanins are polyphenol compounds that give purple potatoes their color, and are known for its antioxidant, anti-inflammatory, and vasodilatory properties. Hence, this work aims to generate novel evidence on the cardiovascular benefits of Peruvian purple flesh potatoes that could lead to its inclusion on preventive dietary strategies and enhance the value of local agriculture. Moreover, as purple flesh potatoes have unique anthocyanins such as petunidin and peonidin whose metabolization has not yet been studied, understanding their metabolization and bioavailability will aid in a better understanding of their observed impact on health.

The study is designed as a randomized, controlled, crossover nutritional intervention involving 30 male prehypertensive participants aged 18-40 (BMI < 30 kg/m2, 120-139 mmHg SBP and/or 80-89 mmHg DBP), with an expected final sample of 21. Each participant will consume a daily portion over a four-week period of potato purée of either purple- or white-fleshed varieties according to the corresponding treatment, with a one-week washout period between treatments. The portion will consist of a rehydrated purée derived from freeze-dried steamed tubers equivalent to 400 grams of fresh weight. All measurements will be taken before each treatment period beginning and after its ending. Anthropometry measurements will include waist circumference, height and weight to calculate BMI. Blood pressure will be measured at fasting and postprandial state. Blood samples will be taken at fasten state for measuring biochemical markers glucose, lipid profile, creatinine, C-reactive protein, and antioxidant capacity. Saliva samples will be taken at fasten state for microbiome analysis. Blood samples for plasma metabolomic analysis will be taken at fasten state before the intervention as a basal measurement and after potato consumption (1 postprandial hour) on the treatment last day. Dietary intake and physical activity will be monitored using 24-hour recall and IPAQ short form questionnaires.