As one dermatologist observed that "nails can be windows to your health”. So symptoms of dry, brittle, ridged or peeling nails could indicate other internal conditions. There are 5 common factors impacting nail health which are: 

1. IRON DEFICIENCY : Vegetarians are at risk for this condition because the iron in plants is not as bioavailable as animal iron. Other than opting for sources of heme-iron (the kind found in hemoglobin) such as dark turkey meat (49% per 6 oz.portion), plant iron bioavailability can be increased when consumed with vitamin C sources, such as kiwi fruit, oranges, strawberries, bell peppers, etc.
Top plant iron sources include: 

• 1 cup cooked beans: soy (111%), white (98%), lentils (82%)
• 1 cup cooked spinach (80%)
• 1 cup cooked oat bran (64%)
• 1 cup soymilk (34%) 

2. EXCESSIVE HAND WASHING-SANITIZING AGENTS : While hand washing is the best way to keep infections and germs at bay, an unfortunate side effect is drying out the nail bed. Moisturizing after cleaning can help mitigate this factor. 

3. EXCESSIVE SELENIUM INTAKE : Most Americans get more than enough selenium to meet requirements (55 micrograms per day). Ingesting too much selenium – as much as 400 micrograms per day – over a long period of time can cause a condition called selenosis, whose chief symptoms are brittle nails and hair. It would be easy to exceed selenium requirements by consuming too many foods particularly high in selenium such as Brazil nuts (1 oz., 989%) or seafood (6 oz.tuna 144% or 3 oz.oysters 238%). 

4. PSORIASIS : Roughly 7.5 million Americans are afflicted with psoriasis, the non-contagious skin condition often characterized by inflamed, scaly lesions on the elbows, knees and scalp. Up to half of these sufferers have psoriasis of the nails too, which can result in discoloration, pitting and lines on the nails. Obesity increases the risk of psoriasis – so losing weight might help. Also there’s some evidence that topical vitamin D may benefit this condition. 

5. B VITAMINS : Some recent research has associated improved nail strength with increased biotin (aka vitamin B7) intake. Unfortunately, the levels needed to observe an effect are about 1,000 times higher than the top food source (egg yolks). Obtaining these amounts from food would be impossible.

While it’s tempting to tweak our exterior – skin, nails, hair – with topical remedies, we believe in beauty from the inside out.