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Does human growth hormone slow the aging process?

Effects of Aging on the Body

­From birth all the way to death, our bodies are constantly changing. Let's take a look at what happens as we age. When you have a normally functioning pituitary gland, human growth hormone (HGH) contributes to these processes.

As soon as we're born, we start developing our muscle strength and nervous system. One of the first things we learn to do as babies is focus our eyes. By the age of two, our vocabulary begins taking shape. As toddlers and children, we begin developing finer muscle control and motor skills. Later, puberty causes quick growth and hormonal changes. As we move into adulthood, we stop growing and reach physical maturity. We have HGH to thank for most of these developments.

In our 30s and early 40s, the level of HGH in our bodies begins to decline. Our metabolism slows, causing the "middle-aged spread" that so many people try to avoid. Between the ages of 40 and 65, we see our muscle strength decline, along with our vision and hearing. Our late 50s to early 60s may bring some cognitive decay as well.

Moving into our late 60s and beyond, our skin becomes less elastic. Our joints and bones may become brittle. Medical conditions like heart disease or cancer become more likely as our bodies are unable to repair themselves the way they used to. At this point, the levels of HGH in our bodies are only one-fifth or less of what they were during youth.

Proponents of HGH claim that the hormone can help decline or even reverse this aging process. They say that raising the HGH levels in their bodies has helped them with everything from weight loss to undoing damage from congestive heart failure [source: DeSimone]. Next, we'll see what the medical community thinks.