The following is not a scientific article but I think it makes a few good points about yogurt being healthy for the skin and hair:
Yogurt is associated with the term "probiotics", which means "that which supports and is for life"! Yogurt is a dairy product that is obtained by fermenting milk. This fermentation uses bacteria to transform milk which is a liquid into yogurt which is semi-solid in nature. Yogurt is a proven treasure-trove of enriching elements like zinc, calcium, lactic acid, Vitamins B1, B2, B-6 and B-12, protein, and yeast. It holds rich deposits of friendly bacteria that boost overall health as well as that of the hair and skin. Yogurt has a multitude of benefits that will surely work wonders for your hair and skin problems.
Yogurt has many healthy enzymes and adds natural oils to the skin. It can diminish pore size, a frequent nuisance for the skin, and can improve the overall skin texture, besides adding a healthy glow to your skin. You can also use yogurt to treat your acne and acne scar. Just apply it on the affected area daily for great results. It is rich in zinc, which helps clear your skin. To increase the effectiveness of this treatment, you can take 1 tsp yogurt and 1/4 teaspoon of orange or lemon juice. Mix them and spread the mixture over your face. Let it remain for five minutes, and then wash it off with warm water. Alternatively, you can take 1/2 cup plain yoghurt, add 1 tbsp olive oil and 1-1/2 teaspoon fresh lemon juice, and mix thoroughly. Smooth this paste over your face and leave it on for about ten minutes, then wash it off with warm water.
If you have oily skin, you can use yogurt to exfoliate daily and remove blackheads and whiteheads. Take some rice powder and yogurt, and blend them into a thick coarse paste. Rub it into your skin in little circular movements. Leave it on for a while and rinse it off. One caution however - be very gentle when applying this paste if you have pimple or pimples marks as it may irritate the inflamed skin.
Yogurt is also beneficial in hair care. It can be the base of your conditioner, and is also a gentle cleanser. Yogurt promotes hair growth, and makes it easy to comb hair and get rid of knots. To garner the benefits of yogurt, put about half a cup of whole yogurt in a blender and work it into a smooth paste. Coat your hair with it, wrap your hair in a towel, and then wash your hair thoroughly after about 15 minutes.
You can even prevent frizzy hair with the help of yogurt. Take four tablespoons of plain yogurt and one egg, and mix them well in a bowl. Massage this mixture well into your hair, leave it for ten minutes, and then rinse it off. This conditioner can soften dull hair and add life to it. Besides all this, do eat yogurt and relish it all the way. Don't forget to make yogurt a regular part of your diet!
That is from the website - http://www.dailyglow.com
. I never use yogurt topically but this might be a good idea.
Some yogurts with live and active cultures are expensive, especially Greek yogurt. I get Blended Low Fat Plain Yogurt from Kroger for $2.19. It has the seal of the National Yogurt Association on the carton.