Issue 380：Menopause and metabolic syndrome

The occurrence of heart disease in women before menopause is lower than in men, but after menopause, the risk for both becomes similar. This is likely because the female hormone, estradiol, decreases after menopause, losing its protective effect on the heart. This leads to the development of metabolic syndrome, which worsens health over time.

Metabolic syndrome is a condition harmful to human health, defined as having at least three of the following five conditions:

1. Abdominal obesity: Waist circumference ≥ 90 cm for men, ≥ 80 cm for women.
2. High blood pressure: Systolic pressure ≥ 130 mmHg or diastolic pressure ≥ 85 mmHg.
3. High fasting blood glucose: Fasting blood glucose ≥ 100 mg/dL.
4. High fasting triglycerides: ≥ 150 mg/dL.
5. Low high-density lipoprotein (HDL) cholesterol: Men < 40 mg/dL, women < 50 mg/dL.

Metabolic syndrome is preventable and treatable. If not checked and treated early, it increases the risk of developing diabetes by 6 times, hypertension by 4 times, high cholesterol by 3 times, and the risk of heart disease and stroke by 2 times, potentially leading to chronic illness.

Abnormal Fat Metabolism After Menopause

Before menopause, the average level of estradiol in a woman's blood is 100-250 pg/mL, but after menopause, it drops to 10 pg/mL. Estradiol is made from low-density cholesterol (bad cholesterol) in the ovaries. Before menopause, estradiol helps to utilize this low-density cholesterol. After menopause, as estradiol production ceases, there is no mechanism to reduce low-density cholesterol, leading to an increase in it and raising the risk of cardiovascular disease.

On the other hand, estradiol helps transport fats into mitochondria for oxidation, generating energy. When estradiol decreases, fatty acids are converted into fat, especially accumulating in the hips and lower abdomen. Additionally, with a decrease in androgens after menopause, fat accumulates, leading to obesity and metabolic abnormalities. If lifestyle factors are mostly sedentary with little exercise, fat accumulates in the skin and organs, which is highly detrimental to health.

Research shows that the reduction in androgens is accompanied by an increase in total cholesterol, triglycerides, and low-density cholesterol, along with a decrease in high-density cholesterol. This increases the risk of metabolic syndrome, raising its prevalence to 50%.

When female hormones are deficient, low-density cholesterol, total cholesterol, and triglycerides increase, while high-density cholesterol decreases. The good cholesterol decreases, and the bad cholesterol increases. This is the effect of hormone deficiency leading to metabolic syndrome.

Improving Diet to Reduce Metabolic Syndrome

Postmenopausal women can improve metabolic syndrome by not only exercising more but also focusing on diet:

1. Follow daily dietary guidelines to ensure balanced intake of the six food categories
2. Women need about 1600-1900 kcal per day. It is recommended to reduce daily intake by 300-500 kcal to achieve the target of 1600-1900 kcal, and to limit high-carbohydrate and high-fat foods. A balanced diet, with an emphasis on high-fiber foods such as whole grains and vegetables, is encouraged. Detailed dietary recommendations can be found in the Department of Health’s daily dietary guidelines and menopause nutrition handbook.
3. Increase protein intake
4. To avoid sarcopenia (muscle loss), protein intake is recommended at 1.1 grams of protein per kilogram of body weight per day for postmenopausal women. Good sources of protein include soy products (tofu, soy milk), lean meats (fish, chicken, duck), eggs, milk, and yogurt.
5. Vitamin D
6. Vitamin D has anti-inflammatory properties, regulates cell growth, boosts immunity, and is crucial for calcium and phosphorus balance, as well as bone and muscle health. Deficiency in vitamin D can lead to various diseases, such as hypertension, cardiovascular disease, cancer, infections, and autoimmune diseases. In postmenopausal women, vitamin D can alter fat metabolism. Deficiency is linked to increased blood pressure and triglycerides, while decreasing HDL cholesterol, especially in those with obesity or diabetes. Vitamin D is mainly found in cod liver oil and fatty fish (salmon, mackerel, sardines). It is recommended that postmenopausal women get 10-15 mcg (400-600 IU) of vitamin D per day from their diet. If deficiency is detected by a doctor, supplementation is advised, but it should not exceed 50 mcg (2000 IU).
7. Omega-3 Fatty Acids
8. Many fatty acids can be synthesized from carbohydrates, fats, or proteins, but two essential polyunsaturated fatty acids—linoleic acid (omega-6) and alpha-linolenic acid (omega-3)—cannot be synthesized by the body and must be obtained from the diet. Omega-3 fatty acids are found in oily fish (salmon, sardines, mackerel), fish oil, and flaxseed oil. These fatty acids help dilate blood vessels, regulate fat metabolism, control blood clotting, improve immune responses, reduce inflammation, protect the heart, and increase insulin sensitivity, which can reduce the risk of metabolic syndrome. It is recommended that postmenopausal women get 0.6-1.2% of their total daily calories (about 1-2.5 grams) from omega-3 fatty acids.
9. Antioxidant Nutrients
10. Oxidative stress damages proteins, fats, and DNA, increasing the secretion of pro-inflammatory cytokines, which are common in obesity, diabetes, metabolic syndrome, insulin resistance, atherosclerosis, and cardiovascular disease, contributing to chronic inflammation. Postmenopausal women should consume more antioxidant-rich nutrients such as vitamin A, vitamin C, vitamin E, polyphenols, and isoflavones. These can be found in fresh fruits and vegetables, unrefined whole grains, nuts, and soybeans. They can effectively reduce total cholesterol, low-density cholesterol, triglycerides, and blood sugar. Improving metabolic syndrome through diet is more effective than hormone replacement therapy.

Conclusion

The average age for menopause in women is around 50, but their life expectancy averages 84 years. Therefore, how women live after menopause becomes even more important. Due to the reduction in female hormones, many diseases arise, especially metabolic syndrome, which causes cardiovascular diseases and severely affects quality of life. Thus, women should adopt a healthy lifestyle early on, incorporating exercise and a diet rich in fiber, so they can live healthily and vibrantly in the later stages of life.

Source: Department of Health, Taiwan, (Link: https://health99.hpa.gov.tw/a19468)