Our brain forms an inseparable functional unit with our body. If the brain is diseased, this has consequences for the body and vice versa. In order to understand how Alzheimer’s disease or other forms of dementia affect us and which early warning signals point to a dementia problem, it makes sense to take a look at the brain structure and the first affected brain areas.

Hormones are the messenger substances that brain and body use to communicate. Hormones are produced by hormonal glands in our body (also in our brain) and play a decisive role in almost all processes in the human body. They send stress signals to the cells (stress hormones), decide how our metabolism functions during rest periods (thyroid hormones) and control our reproduction (sex hormones). Human life does not function without hormones. Disturbances in the hormone balance have far-reaching consequences for our health. Hormone balance has also great importance for brain’s health.

In addition, we humans form a microcosm and a symbiosis with the billions of bacteria that live in and on our body. The number of bacteria living in our intestines is bigger than the number of cells we have in our entire body. These bacteria fulfil important functions for us, they help us to digest food, produce vitamins and influence our immune system. In recent years it has become increasingly clear  that disturbances in this sensitive ecosystem, the microbiome, have far-reaching consequences for our health and can make us ill or keep us healthy.

A third important factor influencing brain health is the energy supply to our thinking apparatus.  The brain is the largest energy consumer of the body, so a lack of energy supply is catastrophic for all cognitive and motor performance of humans. Memory performance, cognitive abilities and concentration are all negatively affected.


The increased incidence of depression and dementia is also closely related to insulin resistance in the brain.

Insulin resistance is additionally produced by a lack of physical exercise. In contrast, every kind of physical / muscular activity improves the sensitivity of the insulin receptors and facilitates the transport of glucose into the cell. Even serious cases of insulin resistance can be improved through sport and moderate exercise to a greater extent than through drug treatment.

Another critical factor for the brain and its energy requirements is stress. Stress and its messenger substances (adrenalin, noradrenalin, cortisol) inhibit the release of insulin. In the short term this is a sensible reaction of the body, in the long term it has a devastating effect. The fine tuning of the insulin signal translation is disturbed and at the same time inflammatory messengers such as interleukin 6 and the tumour necrosis factor TNF-α are increasingly released – both poison for the brain.

In a rough overview (picture above), are several elements that have to work together to ensure long-term brain health. The figure shows only a first selection.