Olive oil and mayonnaise are not just good for your salads, they are also good for your hair. Olive oil has been used as a beauty product for centuries -- ancient Greeks, Romans and Egyptians used it as both a hair treatment and styling product. Covering your head with mayonnaise might not sound like the most obvious route to healthy hair and scalp but, with egg as one of the main ingredients, it does make sense; yolks are rich in fats and proteins while egg whites eat bacteria and remove excess oil.

Fight Frizz and Coarse Curls

One of the keys to turning dry, coarse, frizzy hair into shiny, well-formed curls is making sure it’s well moisturized. Olive oil is packed with vitamins A and E, which can penetrate the hair, locking in moisture, and because it’s lightweight, it doesn’t weigh down the curls. Harness the hair-nourishing properties of olive oil either by adding a few drops to your regular conditioner or by using it as a special treatment. Deep condition dry curls by warming half a cup of olive oil then massaging it, a bit at a time, into your scalp and through to the ends of your hair. Cover your hair with a shower cap or plastic wrap, wait for five to 45 minutes, and then shampoo out. It may take a couple of washes to eradicate all the oil. Use a little neat olive oil as a frizz-busting serum on dry curls. Just be careful not to apply too much or it will look greasy.

Grow Long and Strong

Olive oil can be a good ally in the battle against hair loss. Used as a conditioner it can make hair stronger, therefore less likely to be lost through breakages, and more elastic, therefore resistant to styling processes that pull on the hair, such as blow-drying and flat-ironing. Male baldness is most often caused by the hormone DTH, which shrinks follicles, causing them to grow increasingly finer and weaker hair until it’s almost invisible. Olive oil can act as a block to DTH. Make a hair-boosting treatment by mixing olive oil with tea-tree oil -- seven drops of tea-tree oil to every three tablespoons of olive oil. Massage into the scalp, cover with a shower cap and leave on overnight before shampooing as normal in the morning. The tea-tree oil helps alleviate dandruff which can also be a cause of hair-loss.

Add Shimmer and Shine

Before you head to the salon or drugstore for an expensive gloss or protein treatment, think about reaching into the fridge and grabbing a jar of mayonnaise instead. One of its main ingredients is egg, which is packed with hair-repairing proteins. Most brands also contain lemon juice, which is a natural brightener, and vinegar which helps remove any dulling product build-up. Wet your hair, slather on the mayo from root to tip and cover your head with plastic wrap or a shower cap. Wrap a warm towel over the whole lot to trap the heat and encourage the mayonnaise to penetrate the hair. Wait for 15 to 20 minutes before shampooing out, styling as usual and discovering your new, shiny locks.

Fight the Flakes

Dandruff sufferers who have dry or color-treated hair, can find the stripping nature of many anti-dandruff shampoos too harsh. For a more natural and gentle alternative, massage mayonnaise into your scalp. The egg yolks and oils in mayo moisturize dry skin, helping to get rid of the flakes and prevent more from developing, while the bacteria-banishing enzymes in egg whites help keep the scalp clean. Wash your hair, massage a good dollop of mayo all over your scalp with your fingertips, leave it for about 10 minutes then rinse out. If you find the smell of mayonnaise off-putting, add a few drops of vanilla extract or your favorite essential oil.