Men and women: biological differences
The interdisciplinary, scientific approach of gender medicine explores biological and psychosocial differences and similarities between men and women that affect both health awareness and the emergence and perception of, as well as methods of dealing with, diseases. Gender medicine refers to the "bio-psycho-social health model".
What does this mean? On the one hand, the human biology differences of men and women are investigated; on the other hand, how the symptoms, mechanisms and treatment of diseases vary depending on the gender.
In evolutionary and biological terms, physiological diversity has evolved and solidified over time in order to develop the best survival strategy: The biological differences are based on genes, sex chromosomes and sex-specific hormones. Consequently, these reveal both in the anatomy, the sex organs, as well as all organ systems and cells.
What are the physical differences between men and women?
Male and female embryos start responding gender-specifically inside the womb. Epigenetics, i.e. fetal programming through environmental factors, stress, nicotine, alcohol, etc. has different effects on them. For example: If the mother smokes during pregnancy, the risk of hypertension in boys is much higher than in girls. In gestational diabetes, boys also have a higher risk of developing diabetes, but the Girls are more likely to be overweight.
Women vs. men
The physical differences at a glance:
- women are usually smaller, their body mass index (BMI) is lower
- smaller organs
- more body fat (even newborn girls have a higher percentage of body fat compared to their male counterparts)
- smaller percentage of muscles
- less stomach acid
- slower kidney filtering
- less body water (subject to cycle-dependent fluctuations)
- Differences in liver enzyme activity (typical example: alcohol works differently in women and men)
- sex hormones
All of this has implications on how drugs work, for example. Because these are either soluble in water or fat, they are broken down by the kidney or liver and thus metabolized differently by women and men. Metabolism in turn influences effect and side effect.
Differences in metabolism and energy balance
Female metabolism works differently:
- Women use less energy (basal metabolism) because they have fewer muscles. This means: if a man and a woman are about the same size, the same weight, the same age, and eat the same food, the woman will put on more weight than the man.
- less liver fat
- less belly fat, therefore less risk for diseases associated with belly fat
- More favorable fat cell hormones: Women have more favorable fat on hips and legs, which protects against diabetes and cardiovascular disease.
- better insulin sensitivity
- lower fasting blood sugar level
- Gastric absorption of glucose is slower in women. In a sugar stress test, women showed higher blood sugar levels two hours after taking 75 grams of sugar.
- more intense activation of the stress axis (brain-adrenal axis)
Differences in sex hormones
From the onset of menstruation in puberty, hormones in female body develop depending on the cycle. This has the following consequences: Various medications may have different effects depending on the cycle, asthma attacks may occur differently depending on the cycle.
Menopause causes another change in metabolism. In contrast to premenopausal women, postmenopausal healthy women show worse blood sugar and fat metabolism, higher blood pressure and a redistribution of body fat (to a masculine form).
In healthy men of that age (50 plus), metabolic changes are fewer.
Social factors (gender)
Diseases are dependent on gender and life cycle. Women are more sensitive to psychosocial stress. Their metabolic risk is negatively influenced by the following psychosocial risk factors:
- lack of sleep
- shift work
- stress at work (intense workload, little flexibility)
- low level of education
- low social and economic status
Women live longer, but the loss of healthy years of life (over the whole lifespan) is higher in women. In contrast, men live shorter lives, but only to a limited extent because of biological factors. In this regard, lifestyle plays a key role (alcohol, smoking, other hazardous occupations and risk-taking behavior.
Differences in health behavior
- Women are more likely to see a doctor and attend check-ups. The fact that they still live less healthy years suggests that the male model-oriented treatment is not efficient.
- Men consider exercise to be healthier, while women set great store by a healthy diet. It is therefore important to teach women to enjoy more physical activity from the very childhood.
- Women take fewer steps during the day, regardless of age and weight. (10,000 are recommended)
- Smoking and alcohol abuse WERE common among men and are STILL responsible for a substantial part of the gender gap in life expectancy. The situation is changing.
- Stress due to multiple exposures in job and family or as a single parent, affects mainly women.
- Caring is the women's thing: 80% of all nursing occupations are carried out by women, this also applies to care activities within the family.
Smoking and women:
Even if women smoke less, smoking has more negative effects on them than on men. In addition, women smoke differently and for other reasons, such as stress and weight management. Men have less difficulty quitting.
Smoking leads to an increased risk of complications in women:
- heart attack/stroke (25% higher than in men)
- osteoporosis, pregnancy problems
+++ Read in Part 3: What gender-specific approaches does medicine employ? +++
The author Prof. Dr. med. Alexandra Kautzky-Willer, Medical University of Vienna (MedUni Vienna), is the scientific director of the Institute for Gender Medicine in Gars am Kamp, a healthcare facility of VAMED in cooperation with the MedUni Vienna.
These articles might also interest you:
+ "Part 3 - What is Gender Medicine? - Cardiology, body weight, cancer, depression & medications" - from Univ. Prof. Dr. Alexandra Kautzky-Willer
+ "Part 1 - What is Gender Medicine? - The Genders" - from Univ. Prof. Dr. Alexandra Kautzky-Willer
+ "Lose weight in a healthy and sustainable way" - from Dr. univ. med. Alex Witasek