High milk intake poses no cardiovascular hazard
07 Aug 2021
Individuals with increased milk consumption, while likely to have higher body mass index (BMI), appear to have low serum cholesterol levels, a study reports. This suggests that limiting its intake is unnecessary with respect to the risk of cardiovascular disease.
Researchers conducted a Mendelian randomization (MR) study to identify whether there was a causal relationship between milk consumption and cardiometabolic traits using the lactase persistence (LCT-13910 C > T, rs4988235) variant.
The study used data from three large-scale population-based studies (1958 British Birth Cohort [BC], Health and Retirement study [HRS], and UK Biobank), which involved up to 417,236 participants, as well as summary statistics from other consortia-based studies.
In the UK Biobank, individuals who carried the ‘T’ allele of the LCT variant tended to consume milk (p=7.02 × 10−14). Pooled data from the UK Biobank, the 1958BC, the HRS, and consortia-based studies showed that under an additive model, the ‘T’ allele was associated with higher BMI (pmeta-analysis=4.68 × 10−12) but lower levels of total (TC; p=2.40 × 10−36), low-density lipoprotein (LDL-C; p=2.08 × 10−26), and high-density lipoprotein cholesterol (HDL-C; p=9.40 × 10−13).
Meanwhile, in consortia meta-analyses, the ‘T’ allele was linked to a reduced risk of coronary artery disease (odds ratio [OR], 0.86, 95 percent confidence interval [CI], 0.75–0.99) but not with type 2 diabetes (OR, 1.06, 95 percent CI, 0.97–1.16).
The two-sample MR analysis confirmed a causal association between genetically instrumented milk intake and higher BMI (p=3.60 × 10−5) and body fat (total body fat, leg fat, arm fat, and trunk fat; p<1.37 × 10−6), as well as lower levels of LDL-C (p=3.60 × 10−6), TC (p=1.90 × 10−6) and HDL-C (p=3.00 × 10−5).
More studies are needed to confirm the suggested benefits of milk intake in relation to cardiovascular disease risk, according to researchers.