Curd, often called dahi, is a staple of Indian cooking. It’s made by using an edible acidic product, such as vinegar or lemon juice, to curdle milk.

For years, people have also extolled dahi’s strength as a facial mask, claiming its powers for:

Although there’s plenty of anecdotal evidence, there’s little clinical research to support the many benefits claimed.

According to a 2015 review published in the Journal of Alternative and Complementary Medicine, there’s limited evidence that the topical application of fermented dairy products may benefit the skin.

The review indicates, however, that there are few existing studies, and states that further studies are needed.

Advocates often attribute the potential skin care benefits of curd to its lactic acid content.

According to the Mayo Clinic, lactic acid is an alpha hydroxy acid (AHA) that’s often found in nonprescription acne products.

Lactic acid and other AHAs are known to aid in exfoliation, reduce inflammation, and stimulate the growth of smoother new skin.

This may minimize the appearance of:

  • large pores
  • acne scars
  • fine lines
  • sun damage
  • hyperpigmentation

Lactic acid, according to a 2019 study published in the International Journal of Dermatology, can also help hydrate the skin and work as an antioxidant.

Many proponents of natural healing and natural cosmetics suggest using curd as a face mask.

They often suggest mixing the curd with other natural ingredients that have healing and restorative properties.

Popular recommendations include:

  • curd and cucumber, used once weekly (all skin types)
  • curd and tomato, used once weekly (all skin types)
  • curd and turmeric, used once weekly (all skin types)
  • curd and potato, used twice weekly (all skin types)
  • curd and honey, used once weekly (normal to dry skin)
  • curd and besan (gram flour), used once weekly (normal to oily skin)
  • curd and lemon, used once weekly (normal to oily skin)
  • curd and oats, used once weekly (normal to oily skin)
  • curd and orange peel, used once or twice weekly (normal to oily skin)

Other combinations might include:

If you decide to use curd with other ingredients, make sure you use a recipe from a reputable source.

You should also do a patch test by applying the mixture to a small area of skin. If you develop any signs of irritation over the next 24 hours — such as redness, itchiness, and swelling — don’t apply the mixture to your face.

You might hear the words “curd” and “yogurt” used interchangeably.

Although they have a similar appearance and are both dairy-based, curd and yogurt are quite different.

Curd is made by curdling milk with an edible acidic substance, such as vinegar or lemon juice.

Yogurt is created with a yogurt culture, commonly Lactobacillus bulgaricus and Streptococcus thermophilus. The culture causes a bacterial fermentation of the milk.

There isn’t enough clinical research to fully support the anecdotal benefits associated with topical facial application.

If you’re considering adding curd — or one of its many combinations — to your routine, talk to a dermatologist or other healthcare provider to learn how it might affect your specific skin type and its overall condition.