Branched Chain Fatty Acid Content of United States Retail Cow's Milk and Implications for Dietary Intake

Abstract

Branched chain fatty acids (BCFA) have recently been shown to be a major component of the normal human newborn gastrointestinal tract and have long been known to be a component of human milk. Ruminant food products are major sources of fat in the American diet, but there are no studies of milkfat BCFA content in retail milk. We report here the profile and concentrations of BCFA in a representative sampling of retail milk in the 48 contiguous United States (US), and their estimated intake in the American diet. Conventionally produced whole fluid milk samples were obtained from 56 processing plants across the contiguous 48 states. Retail milk samples contain exclusively iso-and anteiso-BCFA with 14-18 carbons. BCFA were 2.05 ± 0.14%, w/w of milkfat fatty acids (mean ± SD), and anteiso-BCFA comprised more than half this total. Based on these data and USDA food availability data, the average per capita BCFA intake of Americans is estimated to be about 220 mg/d from dairy; if current dietary recommendations were followed, BCFA intake would be about 400 mg/d. Adding intake from beef consumption, these estimates rise to approximately 400 and 575 mg/d, respectively. These results indicate that BCFA intake is a substantial fraction of daily fat intake, in amounts exceeding those of many bioactive fatty acids.

Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependent gut microbiota metabolite production

“…These include monomethyl branched-chain fatty acids (mmBCFAs), such as 13-methylmyristate and 15-methylpalmitate. mmBCFAs can be derived from meat and dairy consumption, 22 produced endogenously from branchedchain amino acids (ie, valine, leucine and isoleucine) 23 or be synthesised by bacteria and incorporated into bacterial cell membranes. 24 Targeted quantification of urinary metabolites derived from metabolism by the gut microbiota also reveals a significant separation between omnivores and vegans (figure 3C).…”

High-Throughput Quantitative Lipidomics Analysis of Nonesterified Fatty Acids in Human Plasma

“…High-resolution mass spectrometry, 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 4 which has already been successfully used to study fatty acids metabolism 19,22 , offers a great advantage compared to triple quadrupole instruments, namely the ability to quantify known species while simultaneously screening for unknowns. During the development of our method, we used this technical advantage to expand our NEFA panel, adding biologically important but often neglected BCFA [23][24][25] to classically quantified saturated and unsaturated fatty acids. To the best of our knowledge, this is the first method for the simultaneous quantification of these three types of NEFA in human plasma.…”

Structural characterization of saturated branched chain fatty acid methyl esters by collisional dissociation of molecular ions generated by electron ionization

“…They are also produced by rumen bacteria and are a substantial constituent of rumen tissue and milk. We recently showed that BCFA constitute 2% of fatty acids in the United States milk supply ( 6 ). The most prevalent monomethyl BCFA have branching on the n-2 or n-3 carbons, referred to as iso and anteiso , respectively.…”