Arthritis is one of the most common diseases in the United States. About 23 percent of adults, or 54 million people, in the U.S. alone live with arthritis. It’s a disease that causes joint inflammation and discomfort. Many people report debilitating pain that limits physical activities. With such widespread effects, it’s important to know what causes arthritis so that you can be proactive and avoid activities that could cause pain in the future.

Types of arthritis

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Arthritis comes in many different forms. There are over 100 different types of arthritis that have been identified so far. Together, they are the most common chronic illness in the U.S. The following are among the most common:

  • Degenerative arthritis – the most common type of arthritis. Over time, the cartilage in joints can wear away, causing bone-on-bone contact, which then leads to inflammation and discomfort. This type is also called osteoarthritis.
  • Rheumatoid arthritis – an autoimmune disorder that causes joint inflammation. It can affect different parts of the body.
  • Psoriatic arthritis – a chronic disease that causes inflammation of the skin and joints. The disease typically appears first as skin inflammation in the form of psoriasis. Over time, it develops into joint inflammation.
  • Ankylosing spondylitis – a form of arthritis that specifically affects the spine and sacroiliac joints in the lower back.
  • Reactive arthritis – arthritis caused by an infection in another part of the body. Typically triggered by urinary, genital, or gastrointestinal infections, it shares many symptoms with psoriatic arthritis.
  • Infectious arthritis – this type of arthritis is caused by an infection from microorganisms such as viruses, bacteria, or fungi.


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The telltale signs of arthritis, no matter the type, is redness, inflammation, pain, and stiffness of the joints. It can happen just about anywhere in the body, but the most common area affected is the fingers and hands. As the effects of the disease continue, swelling can become visible. The pain and discomfort can become so great that it can affect the ability to walk, hand strength, and overall joint flexibility.

Some types of arthritis are caused by infections or autoimmune disorders and can therefore affect other parts of the body besides joints. In some cases, it can also cause fevers, swelling of glands, weight loss, fatigue, and can even affect major organs like the heart, lungs, or kidneys.

The causes of arthritis

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Because there are so many types of arthritis, there isn’t a single cause for all of them. Rather, different things can lead to different types of arthritis. There’s still much to learn about arthritis, but common causes are thought to include:

  • Genetics
  • Injuries
  • Metabolic abnormalities
  • Infections
  • Immune system disorders

Unfortunately, most arthritis is believed to be genetic and/or age-related, which means there’s not much you can do about it. Injuries and physically-demanding or repetitive jobs have also been found to be a factor. Of course, as you get older, the more your joints have worked. The harder you work your joints, the quicker they deteriorate and lead to osteoarthritis.

Diet is also closely linked to arthritic symptoms. Meats and foods that are high in sugar are known to increase inflammation. They might not cause arthritis, but if you already have the disease or are showing symptoms, eating these foods certainly won’t help and might even make it worse.

Arthritis prevention

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Although you can’t always stop arthritis completely, there are a few ways to prevent it or, at the very least, slow it down. Diet is one of the best ways to hold off the painful effects of arthritis. Eating food that’s high in Omega-3s has been shown to reduce inflammation. Of course, anything that helps to reduce inflammation is going to be helpful for people with arthritis. Fish like salmon, trout, and sardines are some of the best sources of Omega-3s.

Along with eating anti-inflammatory foods, watching what you eat is also important for controlling weight. The heavier your body is, the more weight your joints have to support, wearing them out faster. If you already have arthritis, being overweight can exponentially add to the pain.

Exercising and staying active can also help to prevent arthritis symptoms. While it may seem counter-intuitive, since working your joints causes them to deteriorate, regular exercise not only helps control your weight, but it can also build muscle around the joints to add strength and to protect them from wear. Low impact exercises like swimming and biking are ideal for people living with arthritis. Stretching is also important to maintain flexibility and range of motion.