Sulfur (Sulphur) is necessary to produce collagen, which is part of the matrix of skin and cartilage. Sulfur is also very abundant in keratin, which is the protein structure of hair and fingernails/toenails and in the amino acids in the cuticles of hair. There is not much research I can find regarding ordinary hair, nail and skin complaints and dietary sulfur or sulfur supplements, but inflammatory and immune system disorders such as rosacea and allergies have shown some clinical responses to sulfur in the diet or as supplements. Adequate daily sulfur intake can certainly help set up a situation for healthier skin, hair, and nails.
©Science-y Hair Blog 2013
The sulfur in our diets comes from soil and water - which then becomes parts of plants, which we eat, or becomes parts of plant-eating animals we eat or animals which eat plant-eating animals (for example, chickens who eat insects). I'm lumping a number of forms of sulfur in foods and water under the general heading "sulfur" to make this more clear. When an obvious sulfur deficiency is established in a group of people and then published in scientific or medical journals, it is usually in malnourished populations who are eating an extremely limited diet - not well-nourished people. The body system most altered (medically) is the immune system and protein production. But for our purposes, protein production includes your hair and skin and finger/toe nails! The majority of research available is based on sulfur-containing amino acids (from protein in foods), not sulfur supplements. ©Science-y Hair Blog 2013
So we have a body of research that tells us we need to consume sulfur from protein-containing foods, and also that sulfur from other sources or from supplements may have benefits of their own. But we cannot substitute one for the other.
So we have a body of research that tells us we need to consume sulfur from protein-containing foods, and also that sulfur from other sources or from supplements may have benefits of their own. But we cannot substitute one for the other.
There is no established "daily requirement" for sulfur in the United States. The Food and Agriculture Organization of the United Nations, World Health Organization and others have suggested 13 mg per kg of body weight per day. A 150 pound person would then require 890 mg sulfur in their daily diet as a bare minimum. Given that eating an abundance of sulfur in foods has virtually no side effects, let's look at sulfur content in foods. ©Science-y Hair Blog 2013
Here is a short list of sulfur per amount of food you might normally eat (for example, one egg, one slice of wheat bread, one apple), all numbers are approximate:©Science-y Hair Blog 2013
Roasted peanuts (10 whole peanuts): 350 mg - about equivalent to 2 tablespoons of peanut butter
Fish and seafood: 200 mg+
Beef (per 100g or 4 oz serving): 200 mg +
Brazil nuts (5) 290 mg
Chicken (per 100g or 4 oz serving): 130-200 mg
Almonds (10 whole): 150 mg
Pork (per 100g or 4 oz serving): 100-200 mg
Cheese (25g or a 1-inch cube): 200 mg
One egg: 180 mg
Wheat bread: 90-150 mg
Walnuts (5): 100 mg
Dried dates (6): 50 mg
Dried figs (2): up to 80 mg
Pasta: around 30 mg
Milk (230 g or 1 cup): 30 mg
Olives (5): 30 mg
Raisins (1 1/2 teaspoons): 20 mg
Raspberries (about one cup): 20 mg
Strawberries (10): 10 mg
©Science-y Hair Blog 2013
Vegetables: A one cup serving of most vegetables (this is the raw measurement - cooked vegetables "shrink" a little) contains between 10 and 80 mg sulfur. Cabbage, broccoli and spinach are on the high end. Onions provide 50 mg per 1/4 of an onion. Lentils, chickpeas and dried beans fall in this range as well. I am not finding a figure for garlic, also high in sulfur - but I'm not one of those people who eats whole cloves of garlic. Not unless there are a team of vampires beating down my door.
Foods with high-sulfur amino acids (for example, cystine and methionine) for which I do not have actual figures and are not included in the above list: tofu, turkey, other game animals
You may get some sulfur in the form of sulfate in your drinking water.
A person who eats a varied, nutritious diet is not likely to be deficient in sulfur. If you are a vegetarian and do not regularly consume eggs or dairy products, if you have a digestive disease which effects your ability to absorb nutrients, or if you do not have a varied diet (including diets restricted because of medical necessity), you may fall a little short on sulfur intake. Good vegetarian sources of sulfur-containing amino acids are nuts and seeds, wheat, and tofu (particularly brands congealed with minerals containing sulfate, in the US, Mori-nu brand is an example).
Methylsulfonylmethane (MSM) is a sulfur supplement which is generally considered very nontoxic. It can have side effects for some people - so do your research if you choose to supplement. It is usually marketed for skin, hair, nails, and joint health.©Science-y Hair Blog 2013
As noted, sulfur supplements have not been proven to speed hair growth, improve hair strength, or to be more beneficial to one hair texture over another. It makes sense that an adequate intake of sulfur will provide you with the sulfur you need to produce healthy skin and hair - and if you don't consume enough, then your skin, hair and nails may be less-than-healthy and less strong than you'd like. Check the list and tally up the foods you eat and see how your diet adds up. I'm thrilled that peanuts are high in sulfur. I love onions and cabbage, but one can only eat so much of them. I'd like to give you figures for drinking water, but this varies tremendously by region, water treatment and so on.
©Science-y Hair Blog 2013
Have you read that soils are depleted in nutrients and therefore foods have fewer minerals? This bit is for the science-lover in you:
Sulfur is concentrated in "topsoil" and in organic matter (biodegrading plants, animals, insects, bacteria and fungi). Sulfur the mineral (S) has to be turned into sulfate (SO4-) by soil microorganisms, which is water-soluble whereas sulfur (S) is not. This happens when the soil is warm and moist. Sulfate can be washed down through the soil when it rains heavily, or washed away with topsoil via erosion.
©Science-y Hair Blog 2013
So when topsoil is lost (as is common all over the world where there is agriculture), the reservoir of sulfur is reduced. When we add insecticides, fungicides, and fertilizers and use machines to till the soil, we change the communities of microbes in the soil and this may create both problems and solutions. For example, some fertilizers improve plant uptake of sulfur. So yes, soils can lose sulfur, or they can be deficient in sulfur to begin with (and sulfur deficiency is very obvious in plants). This is a result of a lot of people living on a small planet. Some fertilizers are salts which use sulfur as part of the salt, therefore providing sulfur to the soil. But in my region, we usually use mainly ammonia (no sulfur) and manure (variable sulfur) to grow mostly maize, soybeans, and hay, much of which are fed to cattle and hogs.
If you decide to increase your intake of sulfur-rich foods, water intake or supplements, keep in mind that any difference which may occur in your hair or fingernails will take months to appear, and it will be in the new growth only.
Robert F. Grimble, 2006. The Effects of Sulfur Amino Acid Intake on Immune Function in Humans. The Journal of Nutrition 136:1660S-1665S
