It's Medical Monday on 'THV This Morning' and we looked at some myths about growing older. We found a great Reader's Digest article that debunked those myths.

Achy joints are unavoidable. Actually, not exercising is what makes achy joints inevitable. Research has found that those who exercised at least once every two weeks for 20 minutes had more cartilage in their knees. It suggests that being physically active made them less likely to develop arthritis.

Your bones become fragile and your posture bends. Osteoporosis is definitely more common in older people, but it's also very preventable. A study of females over 100 years of age found that only 56 percent had osteoporosis, and their average age at diagnosis was 87. Not bad, given these women grew up before the benefits of diet and exercise on bone were understood.

Genes play the biggest role in how you'll age. Untrue. Even if you're born with the healthiest set of genes, how you live your life determines how they behave over your lifespan. Your genes can be changed by what you eat, how much physical activity you get, and even your exposure to chemicals.

Your brain stops developing after age. Studies show that your brain continues to send out new connections and to strengthen existing ones throughout your life - as long as you continue to challenge it. It really is your body's ultimate muscle.

You lose your creativity as you age. Not necessarily.  A study found that older adults who joined a choir were in better health, used less medication, and had fewer falls after a year than a similar group that didn't join. The singers also said they were less lonely, had a better outlook on life, and participated in more activities overall than the non-singing group.

Seniors are always cranky and unhappy. Not quite. When researchers compared them to a group of middle-age people, they found that both groups were just as happy.

What does it all mean? It means there is no universal definition of aging -- and how you'll age is entirely up to you. You can check out this Reader's Digest article for more aging myths debunked.