Though it can be scary to think about, facts are facts: Humans are rapidly changing the planet. The climate is warming, animal species are dying off at an unprecedented rate, and some of our most cherished natural treasures are expected to become unrecognizable in the span of our lifetimes. But it’s not just the aesthetic beauty of nature that’s at stake — human health is affected as well, in ways you might not expect.

There are many ways that the natural environment impacts health and wellness, some of which research has yet to catch up with. But government agencies such as the Environmental Protection Agency (EPA) and Centers for Disease Control and Prevention (CDC) conduct in-depth research with some of America’s top doctors and environmental scientists to warn the public of potential dangers and keep people safe. Though some of these effects are more visible than others, here are some of the ways that the environment impacts human health.

According to the EPA, air pollution can interfere with your heart health and trigger heart attacks, stroke or irregular heart rhythm. The risk is especially high if you have existing heart problems or are already at risk for these conditions. To protect against these effects, the EPA recommends refraining from spending too much time in areas where pollution may be high, such as near busy roads or industrial areas or around a campfire. You should also take steps to reduce your heart risk; here’s what cardiologists advise.

Air pollution can worsen symptoms of asthma and may trigger asthma attacks. According to the EPA, the two key air pollutants that can affect asthma include ozone and particle pollution. Ozone is found in smog and can vary in severity depending on your city. Particle pollution is found in smoke, haze and dusty air. The EPA offers further details on how to prevent the negative effects of these pollutants, but it can be helpful to know which cities are most affected by smog.

Chronic obstructive pulmonary disease, or COPD, is a group of diseases that cause serious problems with breathing and air flow. Emphysema and chronic bronchitis are both types of COPD. According to the CDC, exposure to air pollutants in the home and in the workplace plays a role in the development of COPD and can either cause or worsen these conditions.

According to the Harvard Center for Climate, Health, and the Global Environment, some of the chemicals used in common consumer products — seemingly everything from printer toner to stainless-steel cookware — could have an effect on public health. Plastic products are of special concern if they are produced with phthalates, since these chemical compounds can cause reproductive harm, according to some studies. Some chemicals used in products — including poly- and perfluoroalkyl substances, which the Harvard center warns are linked to cancer, immune dysfunction in children, weight gain, thyroid disease and other adverse health outcomes — can leach into groundwater and end up being consumed through drinking water.

According to the CDC, climate change can actually have a large effect on your seasonal allergies. Even minor changes in temperature can have a big impact on how much pollen plants produce and for how long, and this can worsen symptoms of allergies. Other climate-related environmental changes such as increased rainfall can impact fungi and mold that grow indoors, another common allergen.

Disease vectors are organisms such as fleas, ticks and mosquitos that may carry disease and transmit diseases to humans. Climate change can affect where these vectors travel; as a result, the CDC predicts that diseases will shift to new regions in the coming years. These diseases include Lyme, dengue fever, and West Nile virus, among others.

Though climate change is actually expected to lead to increased rainfall overall, patterns of precipitation will be unpredictable, making drought a serious public health concern in many areas. Droughts can cause dust storms and problems with food production, in addition to increasing the likelihood of other threats such as wildfires and lack of access to clean water.

Climate change or not, the health effects of extreme heat are important to keep in mind. Every summer, hospitalizations due to heat exhaustion occur. Since temperature changes have been occurring globally, however, the CDC reports that American cities have had significant increases in death rates during heat waves. These deaths are the result of not only heat stroke, but also heart disease, respiratory disease and cerebrovascular disease.

Due to climate change, precipitation has increased considerably, as have natural disasters. According to the CDC, precipitation extremes cause nearly 100 deaths per year due to flooding just in the United States. Even after a flood has subsided, other health concerns like mold growth and respiratory infections persist.

Food security is affected by many other many other macro- and microeconomic factors. But on a global scale, climate change could affect both the quantity and quality of food produced and have additional impacts on pricing and distribution. Shortages of certain nutritious foods may occur (a scorching summer was blamed for a crisis in the global wheat supply in 2018, for instance), creating barriers to better nutrition. Prices of certain foods may rise, as well, making it more difficult to access foods that supply key nutrients for health.

Mental health is already a serious health problem in the United States, and climate change could make it worse in a surprising way. An increase in the number of natural disasters, according to the CDC, is likely to cause a serious rise in mental health issues. Suicide rates may increase, as might diagnoses of mental health disorders.

Carbon dioxide emissions affect more than just the quality of the atmosphere — they may actually affect the nutritional quality of crops, as well. According to the CDC, the nutritional value of individual foods is also expected to decline. Grains and soy may end up containing less protein due to carbon dioxide and other emissions. Micronutrients such as calcium, iron, zinc and some vitamins may also decline because of changes in the soil. According to the Harvard Center for Climate, Health, and the Global Environment, recent research has found that extra carbon dioxide can reduce levels of zinc and iron content in staple crops. Nutrient deficiencies in these minerals can result in weaker immune systems and other side effects.

The CDC says that due to climate change, certain areas have already become more susceptible to wildfires. Aside from the clear danger of the fire itself, smoke from wildfires contains particulate matter, carbon monoxide, nitrogen oxides and some volatile organic compounds, which react with other compounds in the atmosphere to worsen ozone. Exposure to smoke has been associated with hundreds of thousands of deaths annually, according to the CDC.

According to the Harvard Center for Climate, Health, and the Global Environment, exposure to the organic form of mercury (methylmercury) can cause cognitive impairment in children and heart health complications in adults. Mercury enters the average American diet through seafood, and though seafood is still a healthy addition to your diet overall, mercury levels in fish are influenced by emissions from mining operations and coal-fired power plants.

Natural gas is one of the major fuels used to generate electric power, and it’s also used in household heating and appliances. But it doesn’t come without its risks. Natural gas leaks can pose danger to the health of residents of surrounding areas by exposing them to methane and benzene. One natural gas leak in California stretched for months from 2015 to 2016; residents reported headaches, dizziness, fatigue, nosebleeds and other symptoms, and 5,790 households had to be evacuated for safety.

Aside from the clear impact fossil fuels have on the environment, their use and production has a significant impact on human health, as well. The pollutants released from burning fossil fuels can lead to early death, heart attacks, respiratory disorders, stroke and exacerbation of asthma, according to the Harvard Center for Climate, Health, and the Global Environment. Of course, there are more factors than pollution that are impacting your heart health each and every day. Here are some tips from cardiologists on which habits to avoid.

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