1.
Effect of a Hop Extract Standardized in 8-Prenylnaringenin on Bone Health and Gut Microbiome in Postmenopausal Women with Osteopenia: A One-Year Randomized, Double-Blind, Placebo-Controlled Trial.
Lecomte, M, Tomassi, D, Rizzoli, R, Tenon, M, Berton, T, Harney, S, Fança-Berthon, P
Nutrients. 2023;15(12)
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Osteoporosis is a bone condition characterized by weakened and brittle bones, leading to an increased risk of fractures. Oestrogens play a vital role in maintaining bone health, whereby oestrogen deficiency elevates the risk of osteoporosis and fractures, particularly in menopausal women due to the decline in oestrogen levels. Phytoestrogens, plant-derived compounds capable of interacting with human oestrogen receptors, have presented an intriguing non-pharmaceutical avenue for preventing bone loss. Other phytoestrogens have received some attention in the field, however, limited human research exists on prenylflavonoids, a phytoestrogens found in hops (Humulus lupulus). This randomized, double-blinded, placebo-controlled trial aimed to investigate the effects of a year-long supplementation of standardised hop extract (8-PN) Lifenol® on bone mineral density in postmenopausal women. Additionally, the study explored potential mechanisms, particularly focusing on changes in gut bacteria. Notably, gut bacteria play a role in bone metabolism and the pathogenesis of osteoporosis. They are also, along with the liver, responsible for converting hops phenols into active phytoestrogenic compounds. The trial was completed by 95 postmenopausal, women with Osteopenia aged 50 to 85. They all received calcium and vitamin D3 tablets in addition either a hop extract (100mcg) or a placebo for 48 weeks. Changes were monitored using DXA scans for bone mineral density (BMD) and bone metabolism, blood samples for markers for bone health, a quality of life questionnaire, gut microbiome testing, and tests for short-chain fatty acid (SCFA) levels. In conclusion, the intake of hop extract confirmed a previously observed trend of a slight increase in total bone mineral density (BMD), in addition to the benefits linked to calcium and vitamin D supplementation. Although there were no significant changes in the composition of gut bacteria and SCFA levels, the hop extract candidates had a higher abundance of specific genera associated with total body BMD, suggesting a potential positive impact. Larger studies are required to validate these findings.
Abstract
Estrogen deficiency increases the risk of osteoporosis and fracture. The aim of this study was to investigate whether a hop extract standardized in 8-prenylnaringenin (8-PN), a potent phytoestrogen, could improve bone status of osteopenic women and to explore the gut microbiome roles in this effect. In this double-blind, placebo-controlled, randomized trial, 100 postmenopausal, osteopenic women were supplemented with calcium and vitamin D3 (CaD) tablets and either a hop extract (HE) standardized in 8-PN (n = 50) or a placebo (n = 50) for 48 weeks. Bone mineral density (BMD) and bone metabolism were assessed by DXA measurements and plasma bone biomarkers, respectively. Participant's quality of life (SF-36), gut microbiome composition, and short-chain fatty acid (SCFA) levels were also investigated. In addition to the CaD supplements, 48 weeks of HE supplementation increased total body BMD (1.8 ± 0.4% vs. baseline, p < 0.0001; 1.0 ± 0.6% vs. placebo, p = 0.08), with a higher proportion of women experiencing an increase ≥1% compared to placebo (odds ratio: 2.41 ± 1.07, p < 0.05). An increase in the SF-36 physical functioning score was observed with HE versus placebo (p = 0.05). Gut microbiome α-diversity and SCFA levels did not differ between groups. However, a higher abundance of genera Turicibacter and Shigella was observed in the HE group; both genera have been previously identified as associated with total body BMD. These results suggest that an 8-PN standardized hop extract could beneficially impact bone health of postmenopausal women with osteopenia.
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Acute Flaxseed Intake Reduces Postprandial Glycemia in Subjects with Type 2 Diabetes: A Randomized Crossover Clinical Trial.
Moreira, FD, Reis, CEG, Welker, AF, Gallassi, AD
Nutrients. 2022;14(18)
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Glucose levels tend to rise postprandially in patients with type 2 diabetes. Flaxseeds are known to have glycaemic control-improving properties and are rich in dietary fibre, alpha-linolenic acid which is an omega-3 fatty acid and phenolic compounds such as phenolic acids, lignans, flavonoids and tocopherols. Therefore, this randomised cross-over clinical trial evaluated the effects of ground raw golden flaxseeds on postprandial glycaemia induced by the consumption of complex carbohydrates in Type 2 diabetic patients. To assess the 2-hour postprandial glycaemic curve, 19 male Type 2 diabetics were randomly assigned either to consume 15 grams of ground raw gold flaxseeds 15 minutes before eating a standardised balanced breakfast or to consume a standardised balanced breakfast without ground flaxseeds. Compared to men who did not consume ground flaxseeds before their breakfast meal, those who ate 15 grams of ground flaxseed were able to lower their postprandial glucose levels by 24% and reduce their peak glucose levels by 17%. In order to generalise the results for the general population, further robust long-term studies are required to examine the beneficial effects of flaxseed on postprandial glycaemic excursions. This study can, however, assist healthcare professionals in implementing dietary strategies that include flaxseed to manage postprandial blood sugar levels in patients with type 2 diabetes.
Abstract
BACKGROUND Postprandial glycemic excursions are associated with impairment control of diabetes mellitus. Long-term consumption of flaxseed can lower blood glucose levels; however, its effects on the postprandial glycemic response remain unknown. Therefore, this study aimed to evaluate the acute effects of raw flaxseed consumption on the 2 h postprandial glycemic curve in men with type 2 diabetes mellitus (T2DM). METHODS This was a randomized crossover clinical trial. Nineteen men with T2DM were randomly assigned a standardized breakfast without (control) or with a previous intake of 15 g of ground raw golden flaxseed (flax). Glycemia was measured at fasting and postprandial at 15, 30, 45, 60, 90, and 120 min. Palatability markers (visual appeal, smell, and pleasantness of taste) and taste intensity (sweetness, saltiness, bitterness, sourness, and creaminess) were evaluated. RESULTS The peak glucose rise and the 2 h AUC glycemic response reduced in the flax group by 17% (p = 0.001) and 24% (p < 0.001), respectively. The glucose peak time, palatability, and taste parameters did not differ between the two groups. CONCLUSIONS Ingestion of 15 g of ground raw golden flaxseed before breakfast decreases the 2 h postprandial glycemic response in men with T2DM.
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Effects of Dietary Phytoestrogens on Hormones throughout a Human Lifespan: A Review.
Domínguez-López, I, Yago-Aragón, M, Salas-Huetos, A, Tresserra-Rimbau, A, Hurtado-Barroso, S
Nutrients. 2020;12(8)
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Phytoestrogens are polyphenolic molecules with a structural similarity to endogenous human hormones. The main dietary source of these plant secondary metabolites is legumes (particularly soy), and to a lesser extent fruits, vegetables, and cereals. The aim of this study was to synthesize the results obtained by human studies and assess the potential hormone-related health effects of dietary phytoestrogens throughout the human lifespan. Literature shows that: - the impact of phytoestrogens can vary according to the life stage. - soy isoflavones appear not to have any influence on sex and thyroid hormones, bone remodelling and insulin-like growth factor. - although phytoestrogens transfer from maternal blood to the foetus, no effects have been observed in early life. - in later stages of childhood, an increase of androgens and decrease of oestrogens associated with dietary phytoestrogens have been observed in girls and boys, respectively. - in adulthood, endocrine changes arising from phytoestrogen consumption are unclear, although goitrogenic [compounds that interfere with the normal function of the thyroid gland] activity has been observed in men. - in premenopausal women results regarding sex hormones, breast cancer protection and bone remodelling are uncertain. Authors conclude that intake of phytoestrogens does have some physiological effects in humans related to hormone regulation, but like hormones, the benefits depend on the stage of life.
Abstract
Dietary phytoestrogens are bioactive compounds with estrogenic activity. With the growing popularity of plant-based diets, the intake of phytoestrogen-rich legumes (especially soy) and legume-derived foods has increased. Evidence from preclinical studies suggests these compounds may have an effect on hormones and health, although the results of human trials are unclear. The effects of dietary phytoestrogens depend on the exposure (phytoestrogen type, matrix, concentration, and bioavailability), ethnicity, hormone levels (related to age, sex, and physiological condition), and health status of the consumer. In this review, we have summarized the results of human studies on dietary phytoestrogens with the aim of assessing the possible hormone-dependent outcomes and health effects of their consumption throughout a lifespan, focusing on pregnancy, childhood, adulthood, and the premenopausal and postmenopausal stages. In pregnant women, an improvement of insulin metabolism has been reported in only one study. Sex hormone alterations have been found in the late stages of childhood, and goitrogenic effects in children with hypothyroidism. In premenopausal and postmenopausal women, the reported impacts on hormones are inconsistent, although beneficial goitrogenic effects and improved glycemic control and cardiovascular risk markers have been described in postmenopausal individuals. In adult men, different authors report goitrogenic effects and a reduction of insulin in non-alcoholic fatty liver patients. Further carefully designed studies are warranted to better elucidate the impact of phytoestrogen consumption on the endocrine system at different life stages.