Be like a vampire. Sleep, stay out of the sun and consume only what is good for you. jk
But to a certain extent this is true. Sleeping allows the body to rest and regain vitality for the next day, not only will your body be physically restored but mentally as well. Being mentally restored will reduce the stress of everyday life. Stress is a major factor of aging. Eyes droop, memory fades and activity level will be low , inversely related with stress levels.
The UV rays from the sun cause premature wrinkles , sunspots and are very bad for skin elasticity. Wear sunblock or stay out of the sun at peak hours.
Eat whole foods, and healthy stuff. You are what you eat.
Exercise, allows blood flow to many parts of the body that need it, providing those areas with nutrients to stay healthy and working well.
Stretch/yoga, keep yourself limber and have proper posture. Many old people have very poor posture and are bent over because of years of remaining in the same few positions all day. Then there are some, Iv'e noticed that are very upright and robust looking because of daily stretching.
Drink lots of water, the body needs water to function properly. Staying hydrated will allow for your organs to work normally.
Keep up as much of a good routine as you can with these things and you can be sure to be healthier and look younger in old age.