I believe depends on individuals.
Up to early 30s still got public call me Ah-Dee.
Hair dresser often asked me if still serving NS cos I always cut short.
And when I renewed my passport at CMPB, the NS boy, before looking at my passport particular, still asked me if I've finished serving my NS. No CSB.
I once thought I'll look young forever. Like the movie Benjamin Button.
But...
Then from mid-30, everything goes down hill. From the first
public who called me "uncle", nobody ever call me Ah-Dee already.
Hearing, eye sight (reading small prints), physique, all deteriorations expedited.
How can be forever young
When there is a live, there will be a death...

The older you are, the decrease of HGH...
You can have young look but your body system can't lying...
If you see Andy lau already in 50s, he has some boyish look...still can see old what...

Pple though I am 25

Maybe can live until 168

HGH, or human growth hormone, also known as somatropin or simply GH, is a peptide hormone produced by the pituitary gland in the brain. A non-steroidal hormone, it regenerates tissues for growth and repair of many cells in the body. Low GH levels cause erratic sleep patterns, bone loss, increased body fat and decreased muscle mass, strength and mental function. According to the Life Extension Foundation, GH declines by 50 percent every seven years after the ages of 18 to 25. There are many ways to naturally increase the body's production of human growth hormone.
NATURALLY INCREASE GROWTH HORMONE
Step 1
Take in only low-glycemic or slow-digesting carbohydrates throughout the day. Low-glycemic examples are apples, pears, oatmeal, sweet potatoes, brown rice or wheat pasta. Simple sugars that are high-glycemic spike insulin levels. Not only does this lead to body-fat storage, but it severely blunts the release of growth hormone.
Step 2
Perform weight-training intensely with high repetitions. The burn you will feel in your muscles is the build-up of lactic acid. Lactic acid signals our bodies to produce more growth hormone. Try a range between 12 and 30 repetitions to reach the lactic threshold.
Step 3
Take the amino acids L-arginine and L-lysine together before exercise and sleep. The combination of these has shown to increase growth hormone production by up to 700 percent. As little as a gram will do, but take 3 to 5 grams for optimal results.
Step 4
Take 0.5 to 5 mg of melatonin before bed. A hormone that governs over sleep patterns, melatonin has been shown to increase growth hormone levels by up to 157 percent.
Step 5
Take 1.5 to 3 g of GABA immediately before bed. GABA, or gamma aminobutyric acid, has been shown to increase growth hormone production by 200 percent.
Step 6
Take 2 to 10 g of glutamine after a workout or before bed. As little as 2 g can significantly boost GH levels.
Step 7
Get adequate sleep to ensure high growth hormone levels. Most of our GH is produced in the first few hours of sleep.
Step 8
Consume a high-protein, low-carbohydrate snack before going to bed. The amino acids will help to boost GH, while avoiding too many carbs will keep insulin at bay so that it cannot inhibit growth hormone production.
THINGS YOU'LL NEED
Low-glycemic carbohydrates
Gym membership
Arginine
Lysine
Melatonin
Glutamine
GABA
Sleep