What does ‘aging’ mean exactly? Aging is the loss or damage of important molecules (e.g. DNA, proteins, enzymes) and the accumulation of abnormal molecules.
In other words, we lose all the good things and gain all the bad stuff!
How we age is determined by how well we repair damaged DNA. If we don’t repair DNA well, we age faster.
What Happens to Your Skin When It Ages?
Skin aging is happening on two levels: what you see (physical) and what you can’t see (biochemical).
Physical Changes Due to Aging
- Sagging or slack skin
- Loss of firmness (tension)
- Thinner or thicker skin (depends on the type of aging – more on this below)
- Loss of fat (this accentuates wrinkles, since there is less ‘cushion’ to support the dermis)
- Rough texture
- Pigmentation (spots, discoloration)
- Uneven tone
- Dull or lackluster skin
- Dilated capillaries (redness)
Biochemical Changes Due to Aging
A reduction in everything good!
- collagen and elastin production (skin loses tensile strength)
- skin’s ability to bind water (skin becomes dehydrated)
- lipid production (skin becomes dry and skin barrier function is weakened)
- blood flow (nutrients get delivered to cells less efficiently)
- energy production (there is less energy for repairing DNA damage)
- Slower cell turnover (skin cells take longer to shed and regenerate)
- Impaired immune function
- Formation of senescent cells (aging cells)
Intrinsic vs. Extrinsic Skin Aging
When you age, there are two kinds of aging processes at work.
Intrinsic aging is genetic or chronological aging. It means we are genetically programmed from birth to age a certain way, and we can’t change it. This is about 10% of the aging process and starts to show up around age 60.
Extrinsic aging is environmental or lifestyle aging. This is about 90% of the aging process and starts to show up around age 30. This we can control by our lifestyle habits.
Intrinsic aging looks different from extrinsic aging. Here are a few comparisons:
|INTRINSIC SIGNS OF AGING||EXTRINSIC SIGNS OF AGING|
|Epidermis thins||Epidermis thickens|
|Dermis and bones shrink (leads to sagging)||Dermis thins|
|Fine wrinkles (after 60)||Coarse wrinkles (as early as 18), deep wrinkles, and furrowing|
|Pigmented spots (lentigenes)||Mottled, uneven pigmentation|
|Fat on face decreases, especially fat pads above eyes and around mouth||Skin growths (actinic keratoses)|
|Glycation, cross-linking of collagen & elastin|
Extrinsic aging is why a young person can look much older for her age, and vice versa. Your lifestyle choices – what you eat and drink, whether you smoke, how much time you spend in the sun, whether you’re stressed, and other lifestyle factors — have a great influence on how you age.
Twin studies are fascinating, because they compare identical twins who’ve led separate lives and look totally different when they’re older. Twin studies are a perfect example of how environmental factors affect aging.