A healthy heart. A long life. How to care for your heart as you age?

15. 09. 2026

Heart • blood vessels • blood • microcirculation

A Healthy Heart and a Longer Life: Why Looking at the Heart Alone Is Not Enough

The heart is the engine of the circulatory system, but it does not work alone. How effectively oxygen and nutrients reach our cells also depends on the condition of our blood vessels, blood pressure, the physical properties of blood, microcirculation, nervous system regulation and the ability of cells to produce energy.

Can a basic heart examination be normal while a person still experiences fatigue, cold hands, palpitations or poor recovery? Yes. The entire circulatory system needs to be considered.

The heart is a pump – but the pump alone is not enough

With every contraction, the heart generates pressure that moves blood through the arteries and smaller vessels until it reaches the capillaries. This is where oxygen and nutrients are delivered to cells and carbon dioxide and other metabolic waste products are removed.

Heartpump

Blood vesselstransport routes

Bloodtransport medium

Cellsfinal destination

A stronger pump alone cannot solve the problem if the transport routes are damaged, blood flow is impaired or blood does not effectively reach the smallest vessels. The heart, blood vessels, blood and cellular metabolism should therefore be viewed as one interconnected system.

What changes in the circulatory system as we age?

Ageing itself is not a disease. However, the properties of blood vessels, blood-pressure regulation, metabolism and the body's response to physical and emotional stress gradually change over time.

Arterial elasticity

Large arteries can gradually become stiffer and less able to absorb the pressure wave generated by the heart. The heart may then have to work against greater resistance.

Endothelial function

The inner lining of blood vessels plays an important role in vessel dilation, blood clotting, inflammation and regulation of blood flow.

Microcirculation

The smallest blood vessels may become less efficient at adjusting blood flow to the changing needs of muscles, nerves, skin and other tissues.

Metabolic health

Insulin resistance, elevated blood glucose, excess body weight, fatty liver and changes in blood lipids become more common with age.

High blood pressure, smoking, diabetes, excess visceral fat, chronic inflammation, oxidative stress and physical inactivity can all contribute to impaired vascular function. These factors can also reinforce one another.

Blood pressure matters – but it is not the only number

When blood pressure remains elevated over time, the heart has to work against greater resistance and the walls of the blood vessels are exposed to increased mechanical stress.

High blood pressure can remain unnoticed for years because it often causes no obvious symptoms. Repeated and properly performed measurements are therefore important.

A single elevated reading does not establish a diagnosis. Stress, recent physical activity, caffeine, pain, talking during the measurement and an incorrectly sized cuff can all affect the result.

Blood must do more than simply circulate

It must travel through progressively smaller vessels until it reaches the capillaries. Blood flow is influenced by factors such as haematocrit, plasma proteins, fibrinogen, hydration, temperature and the ability of red blood cells to change shape.

Blood is therefore not a simple liquid with a fixed viscosity. Its behaviour also depends on flow conditions and the diameter of the blood vessel.

What does “thick blood” actually mean?

Blood rheology describes the physical properties of blood that influence how it flows. When red blood cells pass through the smallest vessels, they need to deform temporarily. Their number is therefore not the only factor that matters – their flexibility, tendency to aggregate and the properties of blood plasma are also important.

🩸 Haematocrit

Haematocrit represents the proportion of red blood cells in the blood and is one of the important factors affecting blood viscosity.

🩸 Fibrinogen and plasma

Plasma proteins and inflammatory processes can influence the behaviour of blood and interactions between blood cells.

🩸 Red blood cell shape and flexibility

Red blood cells are flexible. When passing through very narrow capillaries, they temporarily change shape so they can travel through vessels that may be narrower than the cells themselves.

“Thick blood” is not a medical diagnosis. The expression can refer to very different situations, from dehydration and elevated haematocrit to changes in plasma proteins or blood clotting. These conditions cannot be distinguished simply by looking at a single drop of blood.

Microcirculation determines the final stage of tissue supply

Large blood vessels transport blood to the organs, but it is the arterioles, capillaries and venules that determine whether oxygen and nutrients ultimately reach individual cells.

delivery of oxygen to cells,
transport of nutrients and hormones,
removal of carbon dioxide and metabolic waste products,
regulation of body temperature,
blood supply to muscles, nerves and connective tissues,
creation of suitable conditions for recovery and tissue repair.

Cold hands, fatigue or reduced physical performance may sometimes be associated with blood flow, but these symptoms are non-specific. Similar symptoms can also have other causes, including anaemia, thyroid disorders, medication, low blood pressure or neurological conditions.

Where do mitochondria fit into the picture?

Delivering oxygen and nutrients through the bloodstream is only part of the process. Cells must also be able to use them effectively.

Mitochondria convert energy from nutrients into ATP – an immediately usable form of energy required for muscle activity, nerve function, tissue repair, vascular regulation and many other cellular processes.

Good circulation alone is not enough if cells cannot efficiently produce energy. Likewise, supporting cellular energy metabolism is not enough if tissues do not receive adequate oxygen and essential nutrients.

Stress is more than just a feeling

During a stress response, the sympathetic branch of the autonomic nervous system becomes more active. The heart may beat faster, blood pressure may temporarily rise and blood flow may be redirected according to the body's immediate needs.

A short-term stress response is a normal part of life. Problems may arise when the body remains in a heightened state of alert for prolonged periods without sufficient time for recovery.

Lack of sleep, pain, infection, psychological stress, alcohol, smoking and excessive physical strain without adequate recovery can all contribute to the body's overall stress load.

What can HRV tell us?

HRV – heart rate variability – describes the natural variation in the time intervals between individual heartbeats. A healthy heart does not beat like a perfectly regular metronome. Its rhythm continuously adapts to breathing, body position, physical activity, sleep, stress and the activity of the autonomic nervous system.

HRV can be used as an additional indicator of stress load, recovery, autonomic regulation and the body's response to training or lifestyle changes.

A single HRV measurement does not establish a diagnosis or determine biological age. HRV is influenced by age, breathing, time of day, medication, alcohol, infection, fatigue and the measurement method. Tracking your own trend under similar conditions is generally more informative than comparing a single value with other people.

Seven steps to support your entire cardiovascular system

Know your blood pressure

Measure it correctly and repeatedly. Keep a record of your readings and discuss persistently elevated values with a healthcare professional.

Know your important laboratory values

Important markers may include blood lipids, glucose and HbA1c, a complete blood count, haematocrit and kidney function. Additional tests may be appropriate depending on individual cardiovascular risk. Lipoprotein(a) can also be useful to measure at least once in adulthood, particularly when there is a family history of cardiovascular disease.

Stay physically active

Walking, appropriate aerobic activity, strength training and exercises that maintain balance can support cardiovascular fitness and help blood vessels respond to the changing needs of tissues.

Eat for your blood vessels and metabolism

Prioritise vegetables, naturally fibre-rich foods, high-quality protein sources, fish, nuts, seeds and minimally processed foods. Limit excessive sugar, sugar-sweetened drinks, ultra-processed foods, trans fats and unnecessarily high salt intake.

Prioritise sleep and recovery

Loud snoring, pauses in breathing during sleep, morning headaches or severe daytime sleepiness may be signs of sleep apnoea, which is associated with high blood pressure and increased cardiovascular risk.

Do not smoke – and do not treat alcohol as medicine

Smoking damages vascular function and substantially increases cardiovascular risk. If you do not drink alcohol, there is no reason to start drinking for supposed cardiovascular benefits.

Do not stop prescribed medication on your own

Do not change treatment because of a single measurement or because you temporarily feel better. Medication changes should be discussed with a healthcare professional and based on repeated measurements and your overall health.

Heart health is about the whole system

Cardiovascular health is not determined by a single number. The heart, arteries, smaller blood vessels, blood, metabolism, nervous system and cellular energy production all interact.

Some cardiovascular risk factors, such as age and family history, cannot be changed. Others – including smoking, physical inactivity, high blood pressure, metabolic health, diet and sleep – can often be influenced.

Small healthy habits maintained consistently over many years can make an important contribution to healthy ageing. Regular physical activity, balanced nutrition, adequate sleep and appropriate preventive health checks are fundamental parts of long-term cardiovascular care.

When should you seek urgent medical attention?

Seek urgent medical help if you develop new or severe chest pain or pressure, sudden significant shortness of breath, loss of consciousness, a new irregular heartbeat associated with weakness or dizziness, sudden difficulty speaking, facial drooping, weakness of an arm or leg, or another sudden and significant deterioration in your condition.

General wellness information and home measurements do not replace professional medical assessment, diagnosis or treatment.

Frequently asked questions

Why is high blood pressure dangerous?

Persistently elevated blood pressure increases the workload on the heart and places additional mechanical stress on blood-vessel walls. Over time, it is associated with an increased risk of cardiovascular complications. High blood pressure may remain unnoticed because it often causes no obvious symptoms.

Do cold hands mean poor microcirculation?

Not necessarily. Cold hands can be related to narrowing of blood vessels in the skin, but they are not diagnostic of a circulation problem. Cold temperatures, stress, anaemia, low blood pressure, medication, thyroid disorders and neurological conditions can also cause similar symptoms.

Is higher HRV always better?

Not automatically. HRV needs to be interpreted in the context of age, health status, heart rhythm, medication and measurement conditions. Following your own trend under similar conditions is generally more useful than comparing your HRV directly with someone else's.

Can blood viscosity be determined by looking at a drop of blood?

No. Assessing haematocrit, clotting, inflammatory markers and other properties of blood requires appropriate standardised laboratory tests. Visual examination of a single blood sample does not determine blood viscosity.

What is microcirculation?

Microcirculation refers to blood flow through the smallest blood vessels, including arterioles, capillaries and venules. It plays an essential role in delivering oxygen and nutrients to tissues and removing metabolic waste products.

What is blood rheology?

Blood rheology is the study of the physical properties that influence how blood flows. Important factors include haematocrit, plasma proteins, red blood cell flexibility, cell aggregation and flow conditions within blood vessels.

Can stress affect heart health?

Yes. Stress can temporarily increase heart rate and blood pressure through activation of the autonomic nervous system. Long-term stress can also influence cardiovascular health indirectly through sleep, physical activity, smoking, alcohol use, diet and other behaviours.