Amino Acid Intakes Are Inversely Associated with Arterial Stiffness andCentral Blood Pressure in Women

Abstract

Background: Although data suggest that intakes of total protein and specific amino acids (AAs) reduce blood pressure, data on other cardiovascular disease risk factors are limited.Objective: We examined associations between intakes of AAs with known mechanistic links to cardiovascular health and direct measures of arterial stiffness, central blood pressure, and atherosclerosis. Methods: In a cross-sectional study of 1898 female twins aged 18–75 y from the TwinsUK registry, intakes of 7 cardioprotective AAs (arginine, cysteine, glutamic acid, glycine, histidine, leucine, and tyrosine) were calculated from food-frequency questionnaires. Direct measures of arterial stiffness and atherosclerosis included central systolic blood pressure (cSBP), mean arterial pressure (MAP), augmentation index (AI), pulse wave velocity (PWV), and intima–media thickness (IMT). ANCOVA was used to assess the associations between endpoints of arterial stiffness and intake (per quintile), adjusting for potential confounders.Results: In multivariable analyses, higher intakes of total protein and 7 potentially cardioprotective AAs were associated with lower cSBP, MAP, and PWV. Higher intakes of glutamic acid, leucine, and tyrosine were most strongly associated with PWV, with respective differences of −0.4 ± 0.2 m/s (P-trend = 0.02), −0.4 ± 0.2 m/s (P-trend = 0.03), and −0.4 ± 0.2 m/s (P-trend = 0.03), comparing extreme quintiles. There was a significant interaction between AA intakes and protein source, and higher intakes of AAs from vegetable sources were associated with lower central blood pressure and AI. Higher intakes of glutamic acid, leucine, and tyrosine from animal sources were associated with lower PWV.Conclusions: These data provide evidence to suggest that intakes of several AAs are associated with cardiovascular benefits beyond blood pressure reduction in healthy women. The magnitude of the observed associations was similar to those previously reported for other lifestyle factors. Increasing intakes of these AAs could be an important and readily achievable way to reduce cardiovascular disease risk.

Saturated Fatty Acids and Cardiovascular Disease: Replacements for Saturated Fat to Reduce Cardiovascular Risk

“…Similar findings associating higher protein intake with lower CVD risk were reported in a crosssectional study of 1898 female twins aged 18 -75 y [103]. After adjusting for confounding variables, they found that greater total dietary protein intake (plant + animal, lowest quintile 12.8 ± 1.1% of energy intake, highest quintile 19.9 ± 1.5% of energy intake) was associated with a 3 mm Hg decrease in central systolic blood pressure (P<0.01), a 2.4 mm Hg decrease in mean arterial pressure (P<0.01), and a 1.9 mm…”

“…Leucine, also more common in animal tissues, has been shown to inhibit nitric oxide synthesis in the vascular endothelium, and may also promote insulin resistance [124]. Jennings et al modeled the relationship between seven individual amino acids and blood pressure or indices of arterial stiffness in a cohort of women [103]. Higher intake of all seven amino acids (arginine, cysteine, glutamic acid, glycine, histidine, leucine, and tyrosine) was associated with lower central and peripheral blood pressure.…”

Dietary Serine Intake and Higher Risk of Hypertension: Tehran Lipid and Glucose Study

“…Dietary protein intake has been pointed out for its relation with BP (7-9). As vasoactive properties of dietary protein are likely dependent on its protein and amino acid composition (10), recent studies address the relation of different amino acids with BP (7,8,(10)(11)(12)(13). Two crosssectional studies in the framework of the International Collaborative Study of Macronutrients, Micronutrients and Blood Pressure (INTERMAP) indicate that higher dietary intake of glycine is related to 2-3 mmHg higher systolic BP, and higher intake of glutamic acid is associated with 1.5 and 1 mmHg lower systolic BP and diastolic BP, respectively (7,13).…”

“…Furthermore, serine competes with glutamic acid to cross the blood-brain barrier, so higher dietary intakes of serine may reduce the entrance of glutamic acid to brain, and consequently, decrease the synthesis of BP-beneficial neurotransmitters. Glutamic acid also showed an inverse relation with BP, which may be explained by its contribution on glutathione formation and removing the additional aldehydes (10,13).…”

Dietary protein intake and risk of type 2 diabetes: results from the Melbourne Collaborative Cohort Study and a meta-analysis of prospective studies

“…Participants from the Melbourne metropolitan area were approached with the use of electoral registers, advertisements, and community announcements in the local media including television, radio, and newspapers. Quota sampling was used to achieve the desired numbers in each age strata (40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59), and 60-69 y) by sex. Migrants to Melbourne from Southern Europe were oversampled to make up onequarter of the study population so as to enrich the range of lifestyle and dietary exposures in the cohort.…”