Written by Joyce Smith, BS. This epidemiological study investigates the association between consumption of sulfur amino acids and cardiometabolic disease risk in U.S. adults.
Cardiometabolic disorders represent a cluster of interrelated risk factors, primarily hypertension, elevated fasting blood sugar, dyslipidemia, abdominal obesity and elevated triglycerides. Among these risk factors may be a lack of adequate fruits and vegetables in the diet. Accumulating evidence from animal studies suggest that diets restricting sulfur amino acids are associated with many health benefits including increased longevity 1 and reductions in aging-related diseases and disorders 2,3 such as obesity and insulin resistance (IR) as well as positive changes in blood markers such as insulin, glucose, leptin, and adiponectin 3. Studies also reveal that the diets of most US adults exceed the Recommended Daily Allowance (RDA) for dietary SAA of 12.2mg/kg/day for methionine and 6.6mg/kg/day for cysteine 4. Methionine and cysteine are among the most toxic amino acids 5 and are implicated in an increased risk for chronic disease; 6 however, there are very few human studies on the potential disease risk of consuming foods high in SAAs.
To investigate the hypothesis that lower consumption of SAAs protects against the development of cardiometabolic disease, Dong and colleagues 7 conducted a cross-sectional data analysis involving 11,576 participants recruited from the Third National Health and Nutritional Examination Survey (NHANES 111) study conducted from 1988 to 1994 8. They compiled a composite cardiometabolic risk score based on the biomarker blood levels of participants following a 10-16 hour fast. All participants were free of heart disease and had SAA levels that were at or exceeded the average estimated daily requirement (EDR) of 15mg/kg/day for adults. Biomarkers included blood cholesterol, triglycerides, HDL, C-reactive protein, uric acid, glucose, blood urea nitrogen, glycated hemoglobin, insulin, and estimated glomerular filtration rate (eGFR). The primary outcome was the results of the cardiometabolic disease risk score and its association with dietary SAA levels. A higher risk score indicates a less favorable cardiometabolic profile.
Researchers found that the average intake of SAA consumption of 39.2 ± 18.1mg/kg/day was more than 2.5 fold higher than the EDR of 15mg/kg/day for adults. After accounting for potential confounders, these higher intakes of total SAA, methionine and cysteine, were associated with significant increases in composite cardiometabolic risk scores (Ptrend<0.01). However, in this study, no association was observed between SAA intake and blood pressure, an independent risk factor for CVD.
Study limitations include the cross-sectional study design, the potential bias of the 24-hour food recall and the inability to prove causation. However, study findings did reveal that high dietary SAA intake is associated with every type of food except grains, vegetables and fruit. Diets rich in meat and dairy products contain higher amounts of SAAs while plant-based diets, lower in SAAs, are associated with a reduced risk for cardiometabolic diseases. Given the high intake of SAA among most adults, these findings may have important public health implications for chronic disease prevention. Low sulfur amino acid diets typically contain more plant-derived proteins and suggest that sulfur amino acid reduction may, at least in part, be responsible for the health benefits associated with a plant-based diet and may offer a feasible approach for reducing sulfur amino acid intake.
Source: Zhen Dong, Xiang Gao, Vernon M. Chinchilli, Raghu Sinha, Joshua Muscat, Renate M. Winkels, John P. Richie. Association of sulfur amino acid consumption with cardiometabolic risk factors: Cross-sectional findings from NHANES III. E Clinical Medicine, 2020; 100248 DOI: 10.1016/j.eclinm.2019.100248
© 2019 Published by Elsevie rLtd. This is an open access article under the CCBY- NCND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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Posted March 2, 2020.
Joyce Smith, BS, is a degreed laboratory technologist. She received her bachelor of arts with a major in Chemistry and a minor in Biology from the University of Saskatchewan and her internship through the University of Saskatchewan College of Medicine and the Royal University Hospital in Saskatoon, Saskatchewan. She currently resides in Bloomingdale, IL.
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- Dong Z, Gao X, Chinchilli VM, et al. Association of sulfur amino acid consumption with cardiometabolic risk factors: Cross-sectional findings from NHANES III. EClinicalMedicine. 2020:100248.
