Urinary excretion of sex steroid hormone metabolites after consumption of cow milk: a randomized crossover intervention trial

Abstract

Background Current cow milk production practices introduce considerable levels of pregnancy hormones into the milk. Humans are exposed to these hormones when cow milk is consumed, and this may explain the observed association between cow milk consumption and several hormone-sensitive cancers. Objectives The aim of the study was to evaluate whether cow milk consumption is associated with an increase in urinary excretion of sex steroid hormones and their metabolites in humans. Methods We conducted a randomized crossover intervention feeding experiment. A total of 109 postmenopausal women consumed 1 L of semiskimmed milk (1.5% fat) per day for 4 d and 1 L of whole milk (3.5% fat) per day for 4 d, intersected by 4-d wash-out periods. Sex steroid hormone levels were measured in 24-h urine samples collected at the end of each intervention and wash-out period. Results Estrogens, androgens, and progesterone were detected in the examined milk samples used for our intervention. Although a very high proportion of the estrogens were conjugated, only small proportions of the androgens and progesterone were conjugated. Milk consumption resulted in a significant increase in urinary estrone (E1) excretion, whereas estradiol (E2), estriol (E3), and 16ketoE2 excretion only increased after semiskimmed milk consumption. Urinary pregnanediol glucuronide excretion was not significantly affected. Conclusion Cow milk consumption increases urinary excretion of E1 in humans. Ingestion of semiskimmed milk appears also to raise E2, E3, and 16ketoE2 excretion, but future studies need to confirm these associations. This trial was registered at https://www.drks.de as DRKS00003377.

Short-term serum and urinary changes in sex hormones of healthy pre-pubertal children after the consumption of commercially available whole milk powder: a randomized, two-level, controlled-intervention trial in China

“…The recruitment and implementation of intervention trials in children are difficult; both earlier and later milk-drinking trials used self-control (comparison before and after intervention). 4,6 According to the statistical principle, when the sample sizes of the intervention and the control groups are 1 : 4-4 : 1, the test efficiency for the difference between groups will be the highest. Therefore, we assigned 52 participants to the control and intervention arms at a ratio of 1 : 3.…”

“…The nutrient contents of the milk powder were as follows: moisture, 3.0 g per 100 g; protein, 23.6 g per 100 g; fat, 28.1 g per 100 g; carbohydrate, 42.0 g per 100 g (see detailed information on the milk powder in the ESI Table 1 †). Both earlier 4 and latest 6 studies on the changes in hormone levels after drinking milk were self-control study designs. To study the role of hormones in milk, we tried to find hormone-free commercial food with the same composition as milk as the control but failed due to its complexity.…”

“…However, more comprehensive hormone information in commercial milk has been reported in recent years. 6,33 Michels et al 6 measured progesterone (9.65 ± 0.89 ng mL −1 ), E 1 (148.9 ± 36.7 pg mL −1 ), E 2 (45.1 ± 5.5 pg mL −1 ), and testosterone (127.2 ± 13.3 pg mL −1 ) levels in whole milk, which is widely consumed in Germany. Qu et al in 2017 33 measured the concentrations of 18 sex steroid hormones in raw milk in Tangshan City, Hebei Province, China, by high-performance liquid chromatographytandem mass spectrometry (HPLC-MS/MS).…”

“…2,5 In addition, the concentrations of estrogens and progesterone in whole milk are usually higher than those in semi-skimmed milk (for example, 9.65 ± 0.89 ng mL −1 vs. 4.56 ± 0.48 ng mL −1 of total progesterone). 6,7 Thus, there is ongoing interest in the status of pregnancy-related sex hormones in current commercial milk (especially in whole milk) and their impacts on consumers.…”

Reliability of A Dried Urine Test for Comprehensive Assessment of Urine Hormones and Metabolites

“…Partial list of urine hormones and analytes that can be measured from dried urine Monitoring of hormonal replacement therapy; assessment of ovarian function or precocious puberty; evaluation of dietary effects[19][20][21][22][23] …”