Have you had one of those days where you've woken up, peered into the mirror and been shocked by the puffy eyes, dark circles, acne or patchy skin looking back at you?
Chances are the culprit is your diet.
We've all heard the saying "You are what you eat" but do we really take it seriously?
According to the health and beauty experts, the truth is our beauty is more than just skin deep.
Make-up artist and health advocate Yvette Gray says the fuel we put in our bodies affects our mood, energy levels, health and even our beauty.
"Your skin is the body's largest organ and so this is one place where we can visibly see the result of poor nutrition," she explains.
"Blemishes, dull, puffy skin and dark circles can all result from the ingestion of highly processed foods; fast foods that are full of trans fats; preservatives; too much salt; vitamin deficiency; soft drinks and too much alcohol.
"All of these can impact on your sleep and the efficient functioning of the body in general, which in turn affects your vitality, skin, hair, nails and eyes."
The appearance of your skin and hair is a true indication of how healthy you are, according to Revitalise dietitian and nutritionist Jo Beer.
"Your lifestyle and how you look after your body can have a huge impact on your skin and hair appearance, much more so than how expensive your creams and shampoos are," she says.
Food intolerance expert Sue Dengate says food intolerances are often misdiagnosed as symptoms of ageing.
She says preservatives, colours, synthetic antioxidants and flavour enhancers in food can trigger reactions as diverse as rosacea and acne to chest pain and fatigue.
The renowned Mayo Clinic in the US says some research suggests diets high in processed or refined carbohydrates and unhealthy fats accelerate skin ageing.
If you've got a special event coming up and want to make sure you look your best, there are definitely some foods you should avoid.
"Avoid 'bloaters' like alcohol, gluten, refined sugar and processed, trans-fatty and salty foods, and make sure that your diet is full of protein, vegetables, fruits, fibre and lots and lots of water," Ms Gray recommends.