I am a 14-year-old with a BMI of 21.8. For the past three years, I have noticed that my toenails are taking on a dark shade of purpleish black. Why is this happening, and is there any way to get rid of this dark colour? Also, I have found that I am losing hair drastically. Is there a natural way to improve my hair growth?
JP by email

Common causes of toenails turning black include ill-fitting shoes, fungus, injury and cutting the nail too short. Wearing tight shoes with a narrow toe-box can push the toenail against the wall of the shoe. Also, an injury to the toenail could turn it purple. Purple or black toenails are a common occurrence for runners and people who work out regularly at the gym. To prevent purple toenail, always wear shoes with a wide toe-box. Always trim your nails at moderate levels to prevent the risk of nail injury. You might need to visit a doctor if you suspect any fungal infection or skin rash.

As for your hair condition, it is important that you have a balanced diet. Try eating 10 grams of black sesame seeds in the morning regularly. Also take 10 grams of chyavanaprasam* at bedtime. It would help to consult a doctor to rule out any health conditions.

My six-and-half-year-old son is a very picky eater. He weighs 17.9kg and appears small for his age because he is the shortest in his class. Getting him to have his meals is a struggle. His health too is a matter of concern. Please help.
A.B, by email

At 17.9 kg, he is in the healthy weight range; a healthy height range is 102cm to 128cm, which can vary according to ethnicity.

If your child has plenty of energy and is active, he is most likely healthy. Being picky about food is a normal behaviour trait for many children. There may be times when your son wants to eat only a particular food, and then not want to eat it at all after a few weeks.

Offer your child a variety of nutritious meals and let him choose what to eat. Try to let him explore new foods on his own. Don't force your son to taste new foods. You may need to offer something new several times before he tries it. Children are more comfortable with routines, so set regular meal times, have people use the same seats at the table and make meals pleasant with other family members. Forcing your son to eat will not help to be responsive to his real bodily needs. You may give him ¼ to ½ teaspoon of vaiswanara choornam* mixed with honey or buttermilk as a carminative and digestive.

*Available at shops selling herbal products.