Obesity has long been thought of as the result of 2 simple lifestyle choices: Eating too much and moving too little. But that view isn't complete.

Experts now understand that obesity is a complex disease that is caused by a combination of many factors. Some of these can be changed and some can't. These factors include:

• Genetics. Sometimes inherited genes affect appetite or weight.
• Environment. The food you have access to, the space you have to exercise and the people you spend time with can affect your ability to make healthy choices. People living in poverty, for example, may not have access to resources to keep themselves healthy.
• Lifestyle choices. Food and exercise play a big role in determining your weight. So does your quality of sleep, how you manage stress and how much alcohol you drink.
• Medical conditions. Some conditions, like Cushing's syndrome and hypothyroidism, can cause weight gain.
• Race or ethnicity. Black and Hispanic adults are more likely to have obesity than are white or Asian adults. Experts say this is partly because of systems that make it hard for Black and Hispanic people to have equal access to healthy food and safe places to exercise.
• Life events. Pregnancy, menopause and periods of stress can affect weight.
• Medicines. Certain medicines may have a side effect of weight gain or make it hard to lose weight.

Typically, obesity isn't the result of just 1 or 2 of these factors. It's usually caused by the interaction of several of them together.

How your environment can affect your weight

Making healthy lifestyle choices is more difficult for some people. Not because they are lazy or uninformed but because their environment makes it hard to eat well and get enough physical activity.

Consider your surroundings:

• Are you able to get to a grocery store that has healthy and affordable food?
• Were you taught to eat healthy foods and get exercise from a young age?
• Is it safe to go for a walk in your neighborhood?
• Do you have a high-stress life that causes you to eat more high-fat or sugary foods?

When you look closely, you may see that some of the decisions you make are influenced by where and how you live.

Your choices matter

Some risk factors for obesity, like your genes, race, ethnicity or environment, are beyond your control. But with support, you can still take charge of much of your lifestyle.

Here are 6 small things you can do right now to help manage your weight:

• Start a food and activity diary. Record what you eat and how much you move so you can see areas that need improvement. Most people think they eat less and move more than they actually do. Writing it down will give you a better understanding of your behaviors.
• Cancel your unused gym membership. If getting on the treadmill sounds like a chore, you won't end up doing it. Instead find an activity you can look forward to. Try kickball with coworkers. Sign up for a dance class. Play basketball with your teen at a local park.
• Turn health into a social activity. Tell loved ones about your goals and invite them to join you in cooking a healthy meal or going for a walk. The people around you influence your behavior. Here's your chance to be an inspiration for them.
• Set realistic goals. Pick an area of health that's meaningful to you and work on improving. You might count your steps or the cups of water you drink. Or commit to trying a new vegetable dish each week. Start small and work on improving a little bit at a time.
• Track your weight. You can only change what you measure.
• Tackle your stressors. If stress is making it hard to make healthy choices, then work on managing stress first. Find support through counseling or loved ones. Make time for relaxing activities that also support your health goals, like yoga, walking or cooking.
• Make an appointment with your provider. Your health care team has plenty of resources for helping you reach your weight goals. They may include meal plans, medicines, or meeting with a dietitian or counselor.

Be sure to tell your health care team about barriers in your life that prevent you from making healthy choices, like not being able to afford healthy food or not having a safe place to exercise. Your care team may be able to help you find resources to create a safer, healthier lifestyle.