Washington: A study of over 12,200 Chinese individuals found that eating protein from a variety of sources was linked to a decreased risk of developing high blood pressure. This implies that eating a well-balanced diet rich in protein from a variety of foods can help avoid new-onset hypertension. The article was published in the ‘American Heart Association’ journal. Hypertension, or high blood pressure, affects about half of the population in the United States, and is one of the primary causes of cardiovascular disease. High blood pressure affects the circulatory system if it is not addressed, and it is a major contributor to heart attacks, strokes, and other health problems. “Nutrition may be an easily accessible and effective measure to fight against hypertension. Along with fat and carbohydrates, protein is one of the three basic macronutrients,” said study author Xianhui Qin, M.D., of the National Clinical Research Centre for Kidney Disease at Nanfang Hospital, Southern Medical University in Guangzhou, China.
There is a strong association between poor diet quality and increased risk of cardiovascular disease and death from cardiovascular disease. In its 2021, dietary guidance to improve cardiovascular health, the American Heart Association advises people to eat healthy sources of protein, mostly from plants and may include seafood and low-fat or fat-free dairy products, and, if desired, lean cuts and unprocessed forms of meat or poultry. The American Heart Association recommends eating one to two servings, or 5.5 ounces, of protein daily.
The study authors analyzed health information for nearly 12,200 adults living in China who were part of at least 2 out of 7 rounds of the China Health and Nutrition Survey from 1997 to 2015 (surveys taken every 2-4 years). Participants’ initial survey was used as a baseline, while data from their last round was used as a follow-up for comparison. Participants were an average age of 41 years, and 47 per cent were men. The survey measured dietary intake in three consecutive 24-hour dietary recalls and a household food inventory. A trained interviewer collected 24-hour dietary information over 3 days in the same week during each round of the survey.
Participants were assigned a protein “variety score” depending on how many different protein sources they ate out of eight options: whole grains, refined grains, processed red meat, unprocessed red meat, chicken, fish, egg, and legumes. Each source of protein was given one point, with a maximum diversity score of eight. The researchers next looked at the relationship between protein variety score and new-onset hypertension.
SYSTOLIC (top number) blood pressure greater than or equal to 140 mm Hg and/or diastolic (bottom number) blood pressure greater than or equal to 90 mm Hg, taking blood pressure-lowering medicine, or self-reporting that a physician-diagnosed high blood pressure since their last survey visit were all considered new-onset hypertension.
1. More than 35 per cent of the nearly 12,200 participants developed new-onset high hypertension during follow-up.
2. Compared to participants with the lowest variety score for protein intake (less than 2), those with the highest variety score (4 or higher) had a 66 per cent lower risk of developing high blood pressure.
3. For each of the 8 protein types, there was a window of consumption amount where the risk of hypertension was lower. Researchers described this as the appropriate level of consumption.
4. When the total quantity of protein intake was considered, the amount consumed was divided into five categories (quintiles), from least to most intakes. People who ate the least amount of total protein and those who ate the most protein had the highest risk for new onset of hypertension.
“The heart health message is that consuming a balanced diet with proteins from various different sources, rather than focusing on a single source of dietary protein, may help to prevent the development of high blood pressure,” Qin said.
A limitation of the study is its observational design. Because researchers used prior health information, they could not definitively prove protein intake of any kind or quantity caused or prevented new-onset hypertension.