Updated: Apr 7, 2022
By Melissa Kluczynski, MS
Protein is a macronutrient that supplies the body with calories, or “energy,” and helps the body build and repair cells and tissues. Protein is a major part of our skin, hair, nails, muscle, bone, and internal organs. We typically think of meat and poultry as sources of protein, but did you know that protein also comes from beans, peas, dairy foods, eggs, nuts and seeds, seafood, soy products, whole grains, and vegetables? Some research studies have found that total protein intake is associated with reduced blood pressure but the findings have been inconsistent, and fewer studies have looked at the effects of specific sources of protein on blood pressure. Chun Zhou and colleagues examined the association between the variety and quantity of protein intake from eight major food sources and the risk for new-onset hypertension in a new study published last month in the journal of Hypertension.
Data from 21,117 participants in the China Health and Nutrition Survey (CHNS) without a diagnosis of hypertension at baseline were included. The CHNS is a large ongoing population-based study in China designed to examine factors associated with health status, such as nutrition. Dietary intake was measured by three consecutive 24-hour dietary recalls and a household food inventory. Eight major sources of protein were identified including whole grains, refined grains, processed red meat, unprocessed red meat, poultry, fish, eggs, and legumes. The outcome of the study was new-onset hypertension, defined as systolic blood pressure greater than or equal to 140 mmHg and diastolic blood pressure greater than or equal to 90mmHg, physician-diagnosed hypertension, or receiving antihypertensive treatment during follow-up.
During 6.1 years of follow-up, 35.1% of CHNS participants developed new-onset hypertension. There was a U-shaped relationship between total protein intake and risk of new-onset hypertension, meaning that participants who consumed the most and least amounts of protein were at increased risk for hypertension. This suggests that there is an appropriate level of protein consumption where the risk for hypertension is reduced. There was also a U-shaped association between processed red meat, unprocessed red meat, and poultry intake and risk for new-onset hypertension. Fish had no effect on blood pressure, while increased egg and legume intake were both associated with lower risk of new-onset hypertension. Both high and low intake of whole grains and refined grains were associated with increased risk of new-onset hypertension. Also, consuming a greater variety of proteins was associated with lower risk of new-onset hypertension.
More research is needed to determine how different sources of protein may be affecting blood pressure. The Dietary Guidelines for Americans recommend eating a variety of protein from both plant and animal sources to ensure that the body gets a range of nutrients designed to keep the body functioning well. There are some limitations of this study including the ability of participants to accurately remember their dietary intake over a 24-hour period. Also, this study only included participants from China whose diet (including sources of protein) may be different from people living in other countries. In summary, this study found that increased variety in protein intake was associated with reduced risk of new-onset hypertension in Chinese adults.
Bottom line: Consuming protein from a greater variety of sources may lower the risk for new-onset hypertension. Eating a variety of protein from both plant and animal sources is important for making sure that your body receives all of the necessary nutrients.
Zhou, C, Wu, Q, Ye, Z, et al. Inverse association between variety of proteins with appropriate quantity from different food sources and new-onset hypertension. Hypertension 2022; 79:00-00. DOI: 10.1161/HYPERTENSIONAHA.121.18222.
Melissa Kluczynski holds a Master of Science degree in Epidemiology from the University at Buffalo and she is currently working as a Research Associate in the Department of Cancer Prevention and Control at Roswell Park Comprehensive Cancer Center in Buffalo, NY. Her research interests include chronic disease prevention and women's health.