Nutrition and Cardiovascular Disease

Cardiovascular disease is actually a group of disorders that affect the heart and blood vessels. The most commonly known CVD is coronary heart disease that affects the vessels supplying blood to the heart. This is a leading cause of heart attacks. Other types of CVD include (but are not limited to) cerebrovascular disease (affecting the vessels supplying blood to the brain) and peripheral arterial disease (affecting the vessels supplying blood to the arms and legs).

Longitudinal studies of women navigating the menopausal transition have contributed significantly to our understanding of the relationship between the menopausal transition and the risk of cardio-vascular disease.

Perimenopausal sex hormone changes, increased adipose (fat) relative to other tissues, increased chronic stress, and physical inactivity all increase a woman’s risk of developing CVD. Therefore healthy eating habits can reduce the risk for CVD. [3]

Postmenopausal women not only have higher total low density lipoprotein cholesterol (LDLc) plasma levels, but also the LDL particle itself becomes more dense.[4] This smaller, denser form of LDL is linked to development of heart disease. The high density lipoprotein cholesterol plasma level decreases with the onset of menopause, and the HDL particle itself changes. [5]

Menopause is associated with a progressive increase in total cholesterol, with, in particular, an increase in low-density lipoprotein (LDL), lipoprotein-α and triglycerides and a decrease in high-density lipoprotein (HDL).[6, 7, 8] Therefore, menopausal women are exposed to a more atherogenic lipid profile (one with a greater tendency to promote the formation of fatty plaques in the arteries) than pre-menopausal women. Total cholesterol levels peak in women at 55–65 years of age – about 10 years later than they peak in men.

The increase in risk factors of diabetes, raised cholesterol, the shift in fat distribution and storage leads to a four-fold increased risk in CVD in women in 10 years after the menopause. The belief that this increase is menopause- or estrogen-deficiency-related rather than purely age-related is confirmed by the findings that for post-menopausal women at any age there is an increased risk of CVD.[9]

One study hypothesized that the ‘myoprotective’ effect of the Mediterranean diet could be linked to higher intake of plant-based foods and the potential benefits of the Mediterranean diet on body composition (especially managing body mass index) in postmenopausal women. The presence of antioxidants like beta-carotene and vitamins C and E might protect people from effects of oxidative stress**. Magnesium improves energy metabolism, transmembrane transport, and skeletal muscle function. [10] The Mediterranean diet especially consists of foods that have anti-inflammatory and antioxidant properties. It is associated with a small but significant decrease in blood pressure, reduction of fat mass, and improvement in cholesterol levels and represents an ideal nutritional pattern in menopause.[11]

**Definition: Oxidative Stress

Oxidative stress occurs when there is an imbalance between free radicals (oxygen-containing molecules with an uneven number of electrons that allows them to react chemically with other molecules easily) and antioxidants in your body. Antioxidants are molecules that can give away an electron to a free radical while still staying chemically stable themselves. When the free radical receives the extra electron, it becomes stable and less reactive. Free radicals can cause oxidation – or large chain chemical reactions in your body – because they react so easily with other molecules.

Nutrition and Type 2 diabetes

Type 2 diabetes occurs when the body is unable to properly regulate and use sugar (glucose) as a fuel. This is a long-term condition that results in too much sugar circulating in the bloodstream affecting insulin production that will eventually lead to disorders of the circulatory, nervous and immune systems.

Changes in insulin secretion and insulin sensitivity after the menopausal transition, due in part to hormone changes, can contribute to an increase in diabetes in women. The risk of death from CVD associated with diabetes is higher in women than in men: in the 20-year Framingham study, women with diabetes were 3.3 times more likely to die from CVD than women without diabetes, whereas the risk for diabetic men was only 1.7 times that of non-diabetic men. [12]

Nutrition and Obesity / Weight change

Energy from food is stored in the form of adipose tissue (fat) beneath the skin (called subcutaneous fat) and around the organs (called visceral fat or central adiposity). Women in the perimenopausal transition typically gain weight and experience changes in the composition of their body fat [13]. The increase in body mass index (BMI – one commonly used measure of adiposity), is seen in multiple studies regardless of menopausal status, so menopausal changes are not the only cause. However, the increased storage of central adipose tissue is clearly linked to menopausal stage. As women enter the menopausal transition, their follicle-stimulating hormone levels (FSH) levels start to rise and towards the end of the menopausal transition there is a sharp increase in FSH levels. This occurs at the same time as a rapid increase in the onset of central adiposity, leading to the conclusion that FSH is a fat-stimulating hormone.[13]

Postmenopausal women lose ‘metabolic flexibility’, which is the ability to respond or adapt to changes in metabolic or energy demand according to their activity levels. Metabolic flexibility diminishes due to estrogen reduction and more fat accumulating in central depots. [14]

All this together means that careful healthy nutrition is especially important during the menopausal transition.

Soy Foods / Soy Extracts / Isoflavones / Soy metabolite equol / Phytoestrogens (plant-based estrogens)

Phytoestrogens are compounds that naturally occur in plants and that many women use as an alternative to Hormone Therapy. Phytoestrogens are not estrogens, nor can they be converted into estrogen, but they can mimic or interfere with estrogen. There are five classes of phytoestrogens: isoflavones (soy and soy-based products, legumes), coumestans (beans, clover sprouts), prenylflavanoids (beer, hops), lignans (flaxseed, whole grains, legumes) and stilbens (red grapes, red wine). Their chemical structure is similar to estradiol, the strongest of the three types of estrogen. [15] Hops (Humulus lupulus) is a source of the phytoestrogen 8-prenylnaringenin (8-PN), which is thought to be a more potent phytoestrogen than soy isoflavone. [15a]

Isoflavones are the most important compound of phytoestrogens and are produced almost exclusively by the members of the Fabaceae family – commonly known as the legume or bean family. Soybeans, a member of the Fabaceae family, are a well known source of phytoestrogens and the most studied in terms of impacts on menopausal transition symptoms. Isoflavones also stimulate the production of sex hormone binding globulin (SHBG), which is a protein that carries estrogen throughout the body. [16]
Some phytoestrogens have to interact in the intestines with bacteria to be absorbed. The absorption of isoflavones requires the presence of the intestinal bacteria that enable the hydrolysis (breakdown) of genistein and daidzein into their active components. Due to this, there are suggestions to combine soy isoflavones with lactic acid bacteria to ensure that the soy isoflavones are available for use in the body. [17].

In a systematic review and meta-analysis of phytoestrogen use for vasomotor symptoms among peri- and postmenopausal women, researchers identified 43 randomized control trials (RCT), including one unpublished trial, that tested the effectiveness of dietary soy, soy extracts, red clover extracts, genistein extracts, natural S-Equol, flaxseed, Rheum rhaponticum extract, and hop extract, for at least 12 weeks. Note that the majority of these studies were not able to be combined into a meta-analysis because the methods were too variable and therefore not able to be meaningfully combined.

The authors of this review concluded that the evidence did not support the use of phytoestrogens to reduce the frequency or severity of vasomotor symptoms at the time. More RCTs that use standardized methods, including standardized isoflavone content in soy products under study, are needed to draw definitive conclusions regarding the use of phytoestrogens for menopausal symptoms.[17, 18]

Products that contain phytoestrogens may only have minimal benefits for hot flashes however they may produce other positive health effects, such as reduction of bone loss [19]. Isoflavones exert a limited beneficial effect on cognition however, this effect may be modified by age, gender, ethnicity, menopausal status, and length of treatment [20]. The effects on bone metabolism show a significant decrease in bone resorption process, especially if associated with HRT [21]. When used topically phytoestrogens had a positive effect on vaginal health and painful sex (dyspareunia). [22]

In studies, stomach and bowel problems were more common in women who took phytoestrogens than in those who did not. However, taking isoflavones for up to 12 months of continuous use was found to be safe. [18]

Vitamin E

Vitamin E is a fat-soluble vitamin thought to act as an antioxidant in the body. Few studies have been performed specifically to investigate the effects of Vitamin E on menopausal transition symptoms. One study that investigated the use of vitamin E for menopause symptom reduction had 120 women receiving 800 IU of vitamin E followed (4 weeks) by placebo (4 weeks) or vice versa. Participants reported a decrease of 1 hot flash per day with vitamin E, which the authors found not clinically meaningful (there was no difference that could be identified by physicians in a clinical setting) [23].

In a similar randomized study, 50 women taking 400 IU of vitamin E followed by placebo or vice versa for 4 weeks each, participants showed a reduction of about 2 hot flashes per day and reduced hot flash severity with vitamin E.[24] Based on these limited research results, there is insufficient empirical evidence to make conclusions about the effectiveness of vitamin E supplementation for menopausal symptoms.[18]

The National Center for Complementary and Integrative Health, a division of the National Institutes of Health, states that Vitamin E, taken as high doses found in supplements, may increase the risk of bleeding (including strokes due to bleeding in the brain) and interact with anticoagulant (blood-thinning) medications such as warfarin (Coumadin).[28]

Omega-3 fatty acids supplements

Omega-3 supplements contain polyunsaturated fatty acids (long-chain fatty acids), including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and α-linolenic acid. Two studies looked at the use of omega-3 fatty acids for treatment of menopausal transition symptoms. In one, an 8-week trial of 91 women randomized to placebo or omega-3 supplement (total daily dose: EPA 1,100 mg + DHA 150 mg), vasomotor symptom frequency and intensity were significantly improved with omega-3 compared with placebo. In a second 12-week study, women were randomized to either an omega-3 supplement (n = 177) or placebo (n = 178) and at the same time also randomized into an activity (yoga, aerobic exercise, or their usual physical activity). There were no significant differences found for either vasomotor symptom frequency or severity (bother). [25]

Ammonium succinate (ingredient in Amberen)

Two small studies, funded by the manufacturers of ammonium succinate, found improvements in perimenopause symptoms such as poor sleep, fatigue, loss of interest in sex, joint and muscle pain, hot flashes & night sweats, and a decrease in anxiety compared with the placebo group.

Lactobacillus acidophilus (Menolacto) Probiotics

Lactobacillus acidophilus is a naturally occurring bacterium that is found in the mouth, intestine and vagina. It is a type of probiotic, which are ‘good’ bacteria. Probiotics can be found naturally in foods such as yoghurt, or can be taken as a supplement in the form of capsules, tablets, wafers, powders or vaginal suppositories. L. acidophilus is often taken to help conditions such as bacterial vaginosis (a vaginal infection) or intestinal problems. There are few clinical studies looking specifically at L. acidophilus as a treatment for menopause. One of these, however, assessed women who scored higher than 20 on the Kupperman Index, a menopause diagnostic tool used to score how severely menopause impacts a woman’s quality of life. The results showed improvements in overall quality of life after taking L. acidophilus for 12 weeks. [20]