Planetary Health - healthy planet, healthy people in climate change

What Planetary Health reveals about health and climate

What direct and indirect effects can climate change have on human health? The research branch Planetary Health examines how much our physical and mental health depends on a healthy planet.

Human-caused environmental changes affect the quality of the air we breathe and the water we drink, the quality and quantity of the food we eat. Even our susceptibility to infectious diseases is affected, and entire regions are questioning whether we can continue to live where we live today.

1. What is Planetary Health?

We know that the environment affects our health. Of course, food, drinking water and air quality are important for a healthy life. But did you know that air pollution today causes more deaths worldwide than HIV, malaria and tuberculosis combined?

Planetary Health is a solution-oriented scientific field - and at the same time a social movement. It focuses on analyzing and tackling environmental problems that affect human health and destabilize life on earth.

The result is climate change and the associated multitude of changes:

• The result is climate change and the associated multitude of changes:
• Increasing global mean temperature
• Rising sea levels
• More frequent occurrence of severe storms
• Increased flooding
• Increased drought cycles
• Air pollution
• Decline in biodiversity
• Shortage of arable land and fresh water
• Environmental pollution
• Shifts in cycles in ecosystems.

2. Health consequences of climate change: risks and solutions

2.1. Heat, drought and forest fires

Extreme weather events such as heat, drought and forest fires are increasing worldwide due to climate change. Long periods of drought lead to crop failures and even food shortages. Forest fires and heat waves endanger human lives and pose a high health risk - especially for older people. Our bodies are only designed for a narrow temperature range and the body's own cooling mechanisms such as sweating have their limits. The cardiovascular system is then quickly overwhelmed. The health effects are often not only physical, but are also accompanied by psychological stress such as stress, anxiety, trauma and depression.

2.2. Storms, floods and homelessness

Storms and heavy rain are becoming more frequent and can lead to flooding, flash floods and inundations. People are at risk of death by drowning, they can be injured by hail, loose branches or objects and drinking water can be contaminated. Losing one's own home due to extreme weather leads to homelessness. And here too, increasing mental illnesses are to be expected.

2.3. Food shortages

All of these climatic weather events can destroy agricultural yields and thus lead to food shortages. Malnutrition and undernutrition, which already claim over three million deaths every year, will increase. At the same time, the area used for agriculture is constantly increasing, often due to deforestation - in favor of livestock farming.

2.4. Risk from infectious agents

Currently, around 1.2 million people worldwide die every year as a result of consuming contaminated drinking water. Lack of sanitation facilities as well as floods and storms affect the quality and quantity of drinking water and exacerbate the problem. Pathogens and viruses multiply under these conditions and cause, among other things, severe diarrhea. In addition to the direct consequences of the disease, this also significantly accelerates malnutrition.

Diseases transmitted by insects, snails, ticks and other parasites are also increasing. The transmission time of these disease vectors is changing due to climate change and their geographical distribution area is shifting. The frequency of diseases such as malaria or dengue fever is therefore expected to continue to increase.

2.5. Increased air pollution

Air pollution is often barely visible to the naked eye and its health consequences only become apparent after some time. Nevertheless, its impact is enormous. In poorer countries in particular, air pollution is one of the greatest health risk factors and permanently reduces the quality of life of those affected. But even in Europe it shortens the lifespan by an average of 2 years.

Indoor air pollution has decreased significantly in recent decades, but external pollution from ozone and fine dust remains high. Cancer and lung diseases are the result. Poorer countries in particular, which are driving forward the high-emission industrialization of their economies, are badly affected.

A megacity like New Delhi in India today has pollution levels like London at the height of industrialization in the 19th century. 40 times higher than London today.

2.6. Allergies

Climate change indirectly affects the cardiovascular system and the respiratory tract through a changed environment. This can promote allergies and infectious diseases. Hay fever is already one of the most common illnesses in Europe. Millions of people are affected in Germany alone. Climate change will cause the numbers to continue to rise. With average temperatures generally warmer, the pollen season is getting longer. More and more people are having problems with a runny nose and watery eyes for most of the year. In mild winters, hazel pollen is now released as early as December. Hay fever will therefore no longer only occur in spring and summer.

2.7. Psychological consequences

The increasing confrontation with the effects of climate change will cause negative psychological effects, such as post-traumatic stress disorder, anxiety, but also aggression and depression. The extent and severity of the health consequences depend on individual circumstances.

Studies assume that conflicts will continue to increase due to increasing resource scarcity and climate-related flight and displacement. The number of people who had to leave their homes due to extreme environmental events was 26.4 million in 2023. Depending on climate protection measures, the UN assumes that this number will be between 25 million and one billion by 2050. But here too, the future can still be influenced to a large extent.

3. Solutions for a healthy future: Combining climate protection and health

The Paris climate goals of 2015 have now become a distant prospect. Their central demand to limit global warming to well below two degrees Celsius compared to the pre-industrial era - and even to aim for a limit of 1.5 degrees Celsius - is still being propagated. But the facts tell a different story. The situation for the planet and health is serious, but the development can still be changed. The negative health consequences could be significantly reduced with effective climate protection.

The Paris climate goals of 2015 to limit global warming to well below two degrees Celsius compared to the pre-industrial era with efforts to limit it to 1.5 degrees Celsius”, to strengthen the “ability to adapt to climate change” and to bring “financial flows into line with climate goals”, also count for our future health.

3.1. Eating sustainably and healthily

Planetary Health Research deals intensively with questions about sustainable and healthy nutrition as well as vegan nutrition. Fewer animal products and more vegetables, fruit, legumes, fiber and whole grain products are recommended - the more regional and seasonal, the better.

Unhealthy and unsustainably produced foods increase the risks for people and the planet. On the one hand, current global food production is the greatest threat to our ecosystems and on the other hand, unhealthy diets in many countries cause numerous diseases of affluence and therefore premature deaths. Excessive consumption of red meat leads to an earlier death - but this can easily be changed by the individual.

3.2. Cycling and walking

As hunters and gatherers, people traveled long distances every day to find enough food. Humans are made for movement. Every kilometer we travel on foot or by bike instead of by car is also a real benefit for the environment. So getting on your bike and walking every now and then is twice as worthwhile.

In Germany, a fifth of all emissions are caused by traffic alone. And overall traffic is still increasing significantly. If you can't leave your car at home, you should drive slowly. This significantly reduces pollutant emissions.

3.3. Rethinking urban planning

Cities can use their infrastructure to facilitate environmentally friendly behavior. In order to create living spaces that encourage exercise and non-motorized traffic, better footpaths and bicycle paths are being built in many places. Educational programs in schools and companies help to broaden understanding and initiate individual behavioral changes. And the expansion of green spaces also protects residents from heat.

Far too few inner cities have a high proportion of green spaces. The greenest city in the world is the Icelandic city of Reykjavik, with 410.8 m2 of green space per inhabitant. In addition, ten percent of the city consists of nature reserves. London plans to green half of its urban area by 2050, Sydney wants to have reached 40% by that time. And Copenhagen has been named the most bicycle-friendly city in the world.

3.4. Adapting everyday life to weather conditions

People can adapt their everyday life to challenging weather conditions. This is important in all areas of life and for all population groups, but especially for children, the elderly and those with pre-existing illnesses. In hot countries like Australia, there have long been given government recommendations.

If you experience heat-related symptoms such as dizziness, exhaustion, clouding of consciousness or circulatory problems, you should seek medical help.

3.5. Three-pack: Stabilize the climate, protect health, promote a sustainable economy

But no matter how hard individual people try, the biggest decisions in climate protection remain political. This also becomes clear when you consider that a good 70% of man-made carbon dioxide emissions are attributable to around a hundred coal, oil and gas companies worldwide.

These findings are reflected in the EU's concept: The "European Green Deal" envisages making Europe the first continent to become climate-neutral by 2050 - through sustainable economic growth and accompanied by a green transformation. The WHO has summarized the most important political measures in a manifesto. 

Many experts are advocating a new beginning with a package of measures to stabilize the climate, protect health and promote a sustainable economy. Because these goals do not contradict each other, but are mutually dependent.

3.6. Spread the message

How can we get individuals, companies and governments to drive climate protection forward? Common interests must be found and communicated. Each of us can help. Raise awareness among your fellow citizens, show initiative in mobility, nutrition, water consumption and many other areas. Perhaps you will also get involved in an organization that advocates for these issues.

Media coverage of climate change has steadily increased. Planetary Health is also being discussed more in scientific journals and governments are raising the issue more often in public. Some companies are also starting to change their minds. But the economy is still lagging far behind other sectors. The more people push the message at all levels, the better our future health will be.

Because everything is connected. To understand and respond to these challenges, we need cooperation across disciplines and national borders. Only then can we protect our health and that of our planet.

Learn more about sustainable nutrition in our other articles.

The contents of this article reflect the current scientific status at the time of publication and were written to the best of our knowledge and belief. However, the article cannot replace medical advice or diagnosis. If you have any questions, please contact your general practitioner.