Does smoking age a smoker's skin on the inside too, or only on the outside?
Smoking does not only age the outside of your skin; it damages blood vessels, protective barriers and inflammatory regulation from the inside out. Quitting helps, but some damage, such as atherosclerosis, remains visible for decades.
Smoking visibly ages the skin: more wrinkles, loss of elasticity and uneven pigmentation. That is well documented. But the damage does not stop at the surface.
On the inside, smoking raises inflammatory markers in the blood considerably. This was shown in a study of more than 182,000 people across 22 populations: smokers had significantly higher levels of inflammatory and coagulation markers than people who had never smoked, and the more cigarettes smoked per day, the higher those levels. This kind of low-grade, chronic inflammation accelerates ageing throughout the entire body, including the deeper layers of the skin.
Tobacco smoke also damages the protective barrier of the skin and mucous membranes. That barrier keeps harmful substances out and regulates moisture and immune defence. When it is disrupted, it contributes to inflammatory diseases and accelerates the overall ageing of tissue.
The internal trail extends beyond the skin. Smoking accelerates atherosclerosis: the walls of arteries thicken and calcified deposits form in the coronary arteries. Even thirty years after quitting, that calcium score was still nineteen percent higher than in people who had never smoked. Inflammation and coagulation markers did gradually return to the levels seen in non-smokers after quitting, but that process also took approximately thirty years.
Whether smoking causes extra ageing of the inner skin layers independently of other organs is difficult to separate from the broader bodily damage. That distinction has not been separately quantified in the available studies. What is clear is that the ageing effects of smoking are not superficial -- they are present in the blood, the vessel wall and the cell.
Claims are based on PMID 39604792, 27720464, 35108405 and 40074467. The internal effects (inflammatory markers, atherosclerosis) are well supported by large cohorts. The direct effect of smoking on the deep skin layers independently of other organs is associative and has not been separately quantified in the available abstracts.
What do smoking and alcohol do to the ageing of your skin?
Smoking demonstrably accelerates skin ageing through oxidative stress and inflammation. There are indications for alcohol, but the evidence is too thin for firm conclusions.
Does your body odour change as you get older?
Yes, your body odour changes noticeably with age: from your forties onwards your skin produces a compound that adds a greasy, grassy note, and at the same time you become less able to perceive smells yourself.
Does chronically poor air quality age your skin?
Chronic exposure to air pollution measurably accelerates skin ageing, and the evidence for this is reasonably consistent. If you live or work in a structurally polluted environment, paying extra attention to your skin barrier (a good moisturiser, sun protection) is a worthwhile step.
Does your skin age faster than your organs?
It has not been proven that skin as an organ naturally ages faster than your internal organs, but it is more vulnerable to sun and other external stimuli that measurably raise biological age. Limiting UV exposure is the best-supported way to slow skin ageing.
Does your skin get thicker or thinner as you age?
Your skin thins at two levels with age: that is well established. Retinoid creams have the most support if you want to slow that process; discuss stronger variants (such as tretinoin) with your doctor or dermatologist.
Does fasting or calorie restriction make the skin look younger?
Fasting and calorie restriction appear to protect the skin in animal research, but direct evidence in humans that your skin will look younger as a result is still entirely lacking. It is too early to act on this practically, although nicotinamide (vitamin B3) as a supplement has already been studied in humans for skin cancer prevention.