August 29, 2026, 6:35 am | Read time: 5 minutes
Starting in the third decade of life, the human body undergoes biological changes as part of the natural aging process. Skin texture, the decline in muscle mass, and the diminishing function of the heart and brain–humans cannot yet escape these. Despite these inevitable developments, a healthy lifestyle through exercise and proper nutrition can slow down the deterioration.
Skin
You notice it starting around age 30: The skin is no longer as elastic and firm as it was in your twenties. Over time, visible skin changes appear: small lines that eventually become full-fledged wrinkles, and soon also pigment changes (“age spots”). The process continues but can be somewhat controlled by protecting against external influences that negatively affect cell renewal, such as free radicals from UV rays, smog, and cigarette smoke.
Hair
As we age, hair structure also changes, partly due to hormones. Especially in women, the decrease in estrogen production makes the hair on the head thinner–but it may also cause (unwanted) hairs to appear in new places, such as on the face. In men, the hormone dihydrotestosterone causes hair on the head, as well as on the chest and back, to thin. Graying hair is due to the decline in melanin production, which typically becomes noticeable by the late 30s. Melanin is the pigment responsible for personal hair color.
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Muscles
Starting around age 30, sarcopenia sets in. This means that the muscle mass of the entire body slowly diminishes. The process accelerates at 50 and again significantly at 70. From this point, it would have severe consequences to remain inactive for several days or weeks, such as due to illness-related bed rest. Regular targeted muscle-building training becomes increasingly important (doctors say by age 40 at the latest). However, it’s important to know: Due to the natural atrophy process, the energy metabolism within the muscles responds less quickly to stimuli. In this context, walking speed is intriguing. Studies show that whether we walk slowly or briskly can provide insights into our biological age.
Also interesting: How fast you should walk to protect your heart
Bones
With age, the strength and density of bones decrease, making them more prone to injury. Doctors also refer to age-related changes in the musculoskeletal system, including ligaments, tendons, cartilage, and joints. Hormonal changes and lifelong wear and tear are partly responsible. Additionally, the collagen content, which serves as the body’s structural protein, becomes thinner. Regular exercise, possible vitamin D supplementation, and a balanced, protein-rich diet are essential to counteract this development.
Cardiovascular System
Starting around age 30, the elasticity of blood vessels decreases, affecting heart muscle strength. This process–which technically begins right after birth–continues to progress. The natural decline in muscle mass also affects the heart, which is largely made of muscle. More fat accumulates in the heart as we age. The bronchial tubes lose elasticity, making it harder to exchange gases, meaning less oxygen intake. All of this makes the body less resilient and more susceptible to high blood pressure and other cardiovascular diseases.
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Brain
As we age, brain mass decreases, and changes occur in nerve cells. This makes us more forgetful, slows our ability to process new information, and generally diminishes our cognitive abilities. However, not only age but also lifestyle can affect the condition of nerve cells and brain function. Smoking, alcohol, lack of exercise, and social contacts have particularly negative effects.
Immune System
The slowing of metabolic processes in the body also affects the mucous membranes, which are supposed to fend off pathogens. Wound healing processes slow down, and (immune) cells weaken over the years. In short, the entire immune system becomes less active with advancing age.
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Sensory Organs
Visual acuity and light sensitivity decrease, and the eye finds it harder to adjust to brightness or darkness. Hearing also declines: High-pitched sounds are particularly harder to perceive. Hearing loss typically becomes a problem only after age 65. Even the sense of taste diminishes because the receptors in taste buds don’t function as well over time. Interestingly, sweet flavors are perceived the longest. When the sense of smell declines, it usually has pathological causes and is not due to the natural aging process.
Preventing Inflammation and Slowing Aging
The process cannot be stopped, but the speed and manner in which the body ages can be influenced. According to Dr. Riedl, “silent inflammations” accelerate aging processes. Knowing what triggers or reduces inflammation can help counteract them. There are also many interactions among the factors. Exercise and sports, for example, help maintain muscle strength, which in turn allows for continued active participation in society, benefiting mental well-being. It’s not just about the body aging, but also about how it ages.