Curcumin, vitamin E, genistein, lactic acid bacteria, vitamin B12 and folic acid exhibit mechanisms of action around regulating inflammatory and oxidative stress, offering immunological responses and promoting estrogen production, which may relate to hot flash reduction, the review published in Nutrients concluded.
More than 75% of women experience hot flashes during menopause, brought on by decreased estrogen levels causing the body's thermostat (hypothalamus) to become more sensitive to slight changes in body temperature.
However, the underlying mechanisms still lack full understanding, therefore this new research compiled ingredients involved in various molecular-level processes and signalling pathways associated with hot flashes to broaden data.
Curcumin
Curcumin could improve hot flashes in postmenopausal women, research has suggested, through a reduction in inflammation and oxidative stress as hot flashes have been linked to an increase in low-grade systemic inflammation.
The protective effects of curcumin are linked to the inhibition of oxidative stress through upregulation of proteins SIRT1 and NRF2 and downregulation of the p53/p21 central tumor suppressors pathway.
The authors also suggested that curcumin could confer benefits through through aryl hydrocarbon receptor (AhR) signaling, which is important for immunological responses and inhibiting inflammation through upregulation of the protein interleukin 22 and downregulation of Th17 proinflammatory response.
Vitamin E
Vitamin E is proposed to improve hot flashes through a reduction in inflammation and oxidative stress.
Previous research has found that Vitamin E can improve postmenopausal hot flashes, and while estrogen administration could lead to better clinical effects, vitamin E might serve as an additive to hormone therapy and its alternative in women with contraindications to estrogens.
As research has found an association between hot flash severity and oxidative stress, the authors of the review note that Vitamin E supplementation may also improve antioxidant status in the early years of menopause by increasing total antioxidant capacity (TAC) levels.
Genistein
Genistein, an isoflavone found in soybeans, has the potential to aid in menopausal symptoms because of its estrogen receptors.
The authors propose this could be through the Kisspeptin-GnRH Pathway, in which the protein kisspeptin signals directly to the GnRH neurons through the action of the kisspeptin receptor to release GnRH into the portal circulation.
This in turn stimulates the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the gonadotrophs of the anterior pituitary, and the increase of FSH and LH causes the ovary to produce more estrogen.
Lactic acid bacteria
Lactic acid bacteria such as bifidobacterium, lactococcus, and lactobacillus are potentially able to convert daidzein (dietary soy isoflavone) into equol as a result of intestinal bacterial flora action.
Equol has higher biological activity than daidzein as it can interact with estrogen receptors and thus induce signal transmission in the cell.
In the translation process, the synthesis of biologically active proteins could regulate both hormone levels and oxidative stress, the authors noted.
Vitamin B12 and folic acid
Vitamin B12 and folic acid (vitamin B9) are also suggested nutrients that could be involved in the mitigation of hot flashes through AHR, according to research.
Vitamin B12 is also important in the production of red blood cells and the transport of oxygen which is necessary for temperature regulation, and folic acid has been suggested as a hormone regulator for menopausal women.
“Many food-derived nutrients and their roles as modulators of potential molecular mechanisms may be related to menopausal hot flashes,” the authors concluded, noting that further detailed studies of these relationships may contribute to the development of new therapies for hot flashes in the future.
Commenting independently on the review, Alex Glover, nutritional development lead at health and wellness retail giant Holland & Barrett, noted that black cohosh holds a monopoly in this space due to its registered THR (traditional herbal registration) claim, indicating it has been registered with the Medicines and Healthcare products Regulatory Agency (MHRA).
“The cause of hot flushes is complex and not fully understood, but some potential mechanisms show promise, as highlighted within this review article,” he added.
Although it is important to understand the mechanism of action, he said he is most concerned with the felt impact for the consumer.
“I think often we can get lost in mechanism and forget about the consumer, and if the benefits will be tangible for them based on the best available evidence,” he said.
Journal: Nutrients
doi: 10.3390/nu16050655
“Menopause Hot Flashes and Molecular Mechanisms Modulated by Food-Derived Nutrients”
Authors: Forma, E. Et al.