Being happy promotes a range of lifestyle habits that are important for overall health. Happy people tend to eat healthier diets, with higher intakes of fruits, vegetables and whole grains (1, 2).

A study of more than 7,000 adults found that those with a positive well-being were 47% more likely to consume fresh fruits and vegetables than their less positive counterparts (3).

Diets rich in fruits and vegetables have consistently been associated with a range of health benefits, including lower risks of diabetes, stroke and heart disease (4, 5, 6).

In the same study of 7,000 adults, researchers found that individuals with a positive well-being were 33% more likely to be physically active, with 10 or more hours of physical activity per week (3).

Regular physical activity helps build strong bones, increase energy levels, decrease body fat and lower blood pressure (7, 8, 9).

What’s more, being happier may also improve sleep habits and practices, which is important for concentration, productivity, exercise performance and maintaining a healthy weight (10, 11, 12).

One study of over 700 adults found that sleep problems, including trouble falling asleep and difficulty staying asleep, were 47% higher in those who reported low levels of positive well-being (13).

That said, a 2016 review of 44 studies concluded that, while there appears to be a link between positive well-being and sleep outcomes, further research from well-designed studies is needed to confirm the association (14).

SUMMARY:Being happy may help promote a healthy lifestyle. Studies show that happier people are more likely to eat healthier diets and engage in physical activity.

A healthy immune system is important for overall health. Research has shown that being happier may help keep your immune system strong (15).

This may help reduce your risk of developing colds and chest infections (16).

One study in over 300 healthy people looked at the risk of developing a cold after individuals were given a common cold virus via nasal drops.

The least happy people were almost three times as likely to develop the common cold compared to their happier counterparts (17).

In another study, researchers gave 81 university students a vaccine against hepatitis B, a virus that attacks the liver. Happier students were nearly twice as likely to have a high antibody response, a sign of a strong immune system (18).

The effects of happiness on the immune system are not completely understood.

It may be due to the impact of happiness on the activity of the hypothalamic-pituitary-adrenal (HPA) axis, which regulates your immune system, hormones, digestion and stress levels (18, 19).

What’s more, happy people are more likely to take part in health-promoting behaviors that play a role in keeping the immune system strong. These include healthy eating habits and regular physical activity (17).

SUMMARY:Being happy may help keep your immune system strong, which might help you fight off the common cold and chest infections.

Being happy may help reduce stress levels (20, 21).

Normally, excess stress causes an increase in levels of cortisol, a hormone that contributes to many of the harmful effects of stress, including disturbed sleep, weight gain, type 2 diabetes and high blood pressure.

A number of studies demonstrate that cortisol levels tend to be lower when people are happier (22, 23, 24).

In fact, one study in over 200 adults gave participants a series of stressful lab-based tasks, and found that the cortisol levels in the happiest individuals were 32% lower than for unhappy participants (25).

These effects appeared to persist over time. When the researchers followed up with the same group of adults three years later, there was a 20% difference in cortisol levels between the happiest and least happy people (26).

SUMMARY:Stress increases levels of the hormone cortisol, which can cause weight gain, disturbed sleep and high blood pressure. Happy people tend to produce lower levels of cortisol in response to stressful situations.

May Protect Your Heart

Happiness may protect the heart by reducing blood pressure, a major risk factor for heart disease (27, 28).

A study of over 6,500 people over the age of 65 found that positive well-being was linked to a 9% lower risk of high blood pressure (29).

Happiness may also reduce the risk of heart disease, the biggest cause of death worldwide (30).

A number of studies have shown that being happy has been associated with a 13–26% lower risk of heart disease (31, 32, 33).

One long-term of 1,500 adults found that happiness helped protect against heart disease.

Happiness was associated with a 22% lower risk over the 10-year study period, even after risk factors were accounted for, such as age, cholesterol levels and blood pressure (34).

It appears that happiness may also help protect people who already have heart disease. A systematic review of 30 studies found that greater positive well-being in adults with established heart disease lowered the risk of death by 11% (35).

It is important to note that some of these effects may have been due to an increase in heart-healthy behaviors such as physical activity, avoiding smoking and healthy eating habits (1, 2, 10, 36).

That said, not all studies have found associations between happiness and heart disease (37).

In fact, a recent study that looked at nearly 1,500 individuals over a 12-year period found no association between positive well-being and the risk of heart disease (38).

Further high-quality, well-designed research is needed in this area.

SUMMARY:Being happier can help lower blood pressure, which may decrease the risk of heart disease. However, more research is required.

May Lengthen Your Life Expectancy

Being happy may help you live longer (31, 39).

A long-term study published in 2015 looked at the effect of happiness on survival rates in 32,000 people (40).

The risk of death over the 30-year study period was 14% higher in unhappy individuals compared to their happier counterparts.

A large review of 70 studies looked at the association between positive well-being and longevity in both healthy people and those with a pre-existing health condition, such as heart or kidney disease (41).

Higher positive well-being was found to have a favorable effect on survival, reducing the risk of death by 18% in healthy people and by 2% in those with pre-existing disease.

How happiness may lead to greater life expectancy is not well understood.

It may be partly explained by an increase in beneficial behaviors that prolong survival, such as not smoking, engaging in physical activity, medication compliance, and good sleep habits and practices (10, 36).

SUMMARY:Happier people live longer. This may be because they engage in more health-promoting behaviors, such as exercise.

May Help Reduce Pain

Arthritis is a common condition that involves inflammation and degeneration of the joints. It causes painful and stiff joints, and generally worsens with age.

A number of studies have found that higher positive well-being may reduce the pain and stiffness associated with the condition (42, 43, 44).

Being happy may also improve physical functioning in people with arthritis.

One study in over 1,000 people with painful arthritis of the knee found that happier individuals walked an extra 711 steps each day — 8.5% more than their less happy counterparts (45).

Happiness may also help reduce pain in other conditions. A study in nearly 1,000 people recovering from stroke found that the happiest individuals had 13% lower pain ratings after three months of leaving the hospital (46).

Researchers have suggested that happy people may have lower pain ratings because their positive emotions help broaden their perspective, encouraging new thoughts and ideas.

They believe this may help people build effective coping strategies that reduce their perception of pain (47).

SUMMARY:Being happy may reduce the perception of pain. It appears to be particularly effective in chronic pain conditions such as arthritis.

A small number of studies have linked happiness to other health benefits.

While these early findings are promising, they need to be backed up by further research to confirm the associations.

• May reduce frailty: Frailty is a condition characterized by a lack of strength and balance. A study in 1,500 elderly adults found that the happiest individuals had a 3% lower risk of frailty over the 7-year study period (48).

• May protect against stroke: A stroke occurs when there is a disturbance in blood flow to the brain. A study in older adults found that positive well-being lowered the risk of stroke by 26% (49).

SUMMARY:Being happy may have some other potential benefits, including reducing the risk of frailty and stroke. However, further research is required to confirm this.

Ways to Increase Your Happiness

Being happy doesn’t just make you feel better — it’s also incredibly beneficial for your health.

Here are six scientifically proven ways to become happier.

• Express gratitude: You can increase your happiness by focusing on the things you are grateful for. One way to practice gratitude is to write down three things you are grateful for at the end of each day (50).

• Get active: Aerobic exercise, also known as cardio, is the most effective type of exercise for increasing happiness. Walking or playing tennis won’t just be good for your physical health, it’ll help boost your mood too (51).

• Get a good night’s rest: Lack of sleep can have a negative effect on your happiness. If you struggle with falling asleep or staying asleep, then check out these tips for getting a better night’s sleep (52).

• Spend time outside: Head outside for a walk in the park, or get your hands dirty in the garden. It takes as little as five minutes of outdoor exercise to significantly improve your mood (53).

• Meditate: Regular meditation can increase happiness and also provide a host of other benefits, including reducing stress and improving sleep (54).

• Eat a healthier diet: Studies show that the more fruits and vegetables you eat, the happier you will be. What’s more, eating more fruits and vegetables will also improve your health in the long-term (55, 56, 57).

SUMMARY:There are a number of ways to increase your happiness. Getting active, expressing gratitude and eating fruits and vegetables are all great ways to help improve your mood.

Scientific evidence suggests that being happy may have major benefits for your health.

For starters, being happy promotes a healthy lifestyle. It may also help combat stress, boost your immune system, protect your heart and reduce pain.

What’s more, it may even increase your life expectancy.

While further research is required to understand how these effects work, there’s no reason you can’t start prioritizing your happiness now.

Focusing on the things that make you happy will not only improve your life — it may help extend it too.