If those under eye circles are looking a little darker than usual, our usual response is to reach for the light reflecting concealer. If our lips are feeling a little dry, we blame it on the weather and slick on an extra layer of lip balm.
However it's often worth taking a closer look - our bodies might just be trying to tell us something.
If your lips are constantly dry, you're probably not drinking enough water, but it can also be a sign that you're not getting enough vitamin E, which can be found in peanuts, leafy greens and seeds.
Dry lips might also indicate a lack of vitamin B, which helps to maintain the health of your cells, and in turn, the condition of your skin.
In extreme cases, cracked, dry skin at the corner of the mouth can indicate a B-6 deficiency. Beans, peanuts, squash, beef and leafy vegetables are all rich in B vitamins.
Few people look their best after a night on the town, but a severe case of bed head and morning breath bad enough to clear whole rooms are often just the tip of the iceberg.
When we drink alcohol, our bodies divert oxygen and blood to the liver and other crucial organs to help our bodies process the alcohol more effectively. As a result, our skin inevitably suffers due to decreased circulation, leaving us looking pale and washed out.
Another side effect is the widening of blood vessels. "If you've ever observed a person who has consumed several drinks, you may have noticed a flushing across their face," points out Amanda Griggs, director of health programmes at Chelsea's Balance Clinic.
"This is due to the widening of blood vessels and broken capillaries throughout the skin. Alcohol can also worsen the symptoms of rosacea, and lead to the dilation of blood vessels. Repeated overindulgence can cause the vessels to dilate permanently, causing red, spidery veins."
Alcohol also depletes our body's ability to fight free radicals. "Free radicals accelerate the deterioration of collagen and elastin, which eventually leads to the emergence of fine lines and wrinkles," warns Angela. Free radical damage is also caused by smoking, most notably in the form of dull and dehydrated skin. Smoking dehydrates skin and deprives it of oxygen, meaning your skin will quickly lose its radiance as the blood vessels on the upper layers of the skin constrict.
[See also: 10 ways to improve your diet in 2012]
Fast food contains high levels of fat and sodium along with refined carbohydrates, which dry out the skin and can also increase the prominence of wrinkles, due to their tendency to break down our skin's natural elastin supplies.
The rancid fats within fast food can also react with the protein molecules within our cell tissue and cause inflammation leading to swelling and puffiness.
When it comes to sugar, those with a sweet tooth aren't just putting their teeth at risk, but their skin, too. Too much sugar can speed up the degradation of the collagen and elastin supplies which keep our skin strong and supple.
This happens because eating sugar triggers a process known as glycation, which sees the sugar molecules bind to our collagen and elastin fibres, leaving them brittle and more likely to break. This is when wrinkles and fine lines appear.
So, we've established what not to do, but what are the things we need to incorporate into our diet in order to look our best? Vitamin C is the ultimate weapon for those waging war on wrinkles. It helps boost the production of collagen, which keeps our skin firm, and also helps our skin to repair itself.
It's also great at protecting skin from the damage caused by free radicals - free radicals being the unstable molecules that damage collagen and cause skin dryness, fine lines and wrinkles.
Heavy drinkers often find vitamin B (found in whole grains such as millet, buckwheat, rye, barley, quinoa, corn and barley) especially beneficial, because alcohol depletes the B vitamins which are especially important for healthy hair, skin and nails.
If you haven't heard of Alpha lipoic acid, it's high time you found out more. It's an antioxidant which occurs naturally in our bodies and can help to generate the cellular energy required to keep our skin looking radiant. Small quantities can be found in sardines, beef, spinach and peanuts and it can also be taken in supplement form.
The properties of zinc are also often underrated. Zinc supplements are often prescribed to patients with bedsores, burns or skin ulcers due to its ability to heal wounds, which it does by boosting the production of collagen.
Zinc can also help improve our body's ability to absorb vitamin A, which is thought to slow down the skin's ageing process. Zinc can be found in Shellfish, pecan nuts, turkey, wheat germ, and also as a supplement. However, it's best to avoid taking zinc in supplement form for extended periods of time.
Vitamins B and C aren't the only ones which can work wonders on our skin. Vitamin E has anti inflammatory properties, and can be found in olives, avocados, nuts and seeds.
If you're a heavy smoker or drinker, a spicy curry might not do much for your breath, but the sulphur in foods such as onions, garlic, leeks and eggs can stimulate the production of an antioxidant called glutathione.
This antioxidant enhances the elimination of toxins produced by cigarettes and can also boost collagen production, which is especially important for smokers. Although you could just makes things significantly easier and ditch the cigarettes altogether.