A client with dry, brittle nails will, nine times out of 10, blame the condition on her diet. She’ll claim, “I don’t eat right” or “I don’t get enough vitamins.” Nail technicians may perpetuate the myth of diet-caused nail problems by encouraging clients with these complaints to take vitamin supplements to strengthen their nails.

But nutrition is a much overrated factor in the nails’ condition.

The nail is composed of keratin, a form of protein found naturally in the nails. Nails are protein, which cannot be made from vitamins or minerals. The skin, liver, heart, and brain are all different organs, but they do not each use one specific vitamin. The nails are no different. Vitamin supplements have no specific therapeutic effect on the nail, unless a person is suffering from an extremely rare case of vitamin deficiency.

There are isolated illnesses or physical conditions that may be reflected in the nails’ condition. For example, patients on starvation diets and patients taking anti-cancer or immunosuppressive drugs will often have dry and brittle nails.

Also, patients losing large quantities of protein due to kidney disease will exhibit pale nail beds caused by swelling under the nails. But those individuals don’t need to look to their nails for clues about their health. They already know they have kidney disease by the time it’s severe enough to affect their nails.

Persons with severe anemia and malnutrition can develop spoon nails, though this is rare. I have seen congenital-, traumatic-, and disease-induced spoon nails, but I have never seen a case of spooning due to anemia or malnutrition. This severe malnutrition is most commonly found in the poorest Third World countries. I am not saying Americans have perfect nutrition; rather, the quality of their nutrition does not play a significant role in nail problems.

A person who has suddenly lost a significant amount of weight may have dry and brittle nails. Once the person stops dieting and resumes eating well-balanced meals, the nails return to normal.

Another popular myth is that either calcium or gelatin supplements will strengthen the nails. Calcium is a mineral that makes the bones hard and strong. But just because nails are hard doesn’t make them related to bone. Unlike bones, which are about 67% calcium, nails are two parts calcium per thousand, and calcium supplements will not make them stronger or harder.

Gelatin is another ‘wonder drug.’ Gelatin has been anecdotally recommended in medical literature for years but all scientifically controlled studies show that it has no effect on nails. The notion probably originated because some doctor didn’t want to says, “I don’t have the answer.” Admittedly, the nails’ condition will vary from time to time, influenced by seasons or changing habits. Gelatin gains its ongoing support from those cases where there is no other readily apparent explanation for the change.

Yet, no one argues when told their nails are in poor condition because of a vitamin deficiency. Americans love to take vitamins to be good to themselves. (They have the richest urine in the world.) But there are no specific vitamins to treat the nails; any multiple vitamin can be a nail vitamin, or a hair vitamin, liver vitamin, sex vitamin – or whatever you wish.

I don’t believe any health problems could occur from persons taking a regular mixture of vitamins, but I caution against large doses of any specific vitamin. Because vitamins are available without prescription, they can be abused. Many vitamins become chemicals, or even toxic agents, when taken in large doses.

When a patient comes to me with dry skin, I cannot cure it with diet. I can achieve therapeutic benefits with creams and by advising the patient to avoid overbathing, but I cannot change the dryness. Every 20 to 30 years I might see a patient with hypothyroidism whose resulting dry skin can be helped by thyroid medication, but I must accept that I cannot change the basic nature of dry skin.

Likewise, you should accept that nutrition, except in extreme cases, has nothing to do with the nails. Many people have dry or brittle nails. Sometimes the condition of the nails changes for no apparent reason, perhaps returning to normal after a few months. The medical profession doesn’t know why the changes occur, but we do know they are not caused by poor diet.

Instead of advising the client to take vitamin supplements such as calcium or gelatin, treat the symptoms of dry and brittle nails. Many nail treatments containing protein or amino acids are available. These do not eliminate the problems, but they do offer a protective coating that artificially strengthens the nails.

Orville J. Stone M.D., is a dermatologist practicing in Southern California. He has taught at medical schools for 30 years. He has published 150 scientific papers; his first paper on nail disorders appeared in 1962.

The opinions expressed in this column are the author’s. We invite you to write us with any questions about nail health for discussions in a future column.