How Diet and Nutrition Contribute to a Healthy Head of Hair

From color to texture to style, hair is something unique to everyone that we all can relate to, and is a part of us from a very early age. “Hair follicles begin forming in fetuses around 14 weeks of age, and by 20 weeks downy hairs begin to grow,” says Deborah Cohen, associate professor of clinical and preventive nutrition science at Rutgers University School of Health Professions in Newark.

Cohen explains that hair is made mostly of a protein called keratin, and is formed from a bulb that’s deeply rooted under the skin. The bulb is surrounded by capillaries that supply the bulb with nutrients and oxygen to allow hair to grow.

“These components are necessary for hair growth, and if someone has a nutrient deficiency, it will show through thinning hair or hair loss,” she says.

Considering the Cause

Most commonly, hair thinning or loss is seen in those who are deficient in protein, which is one of the main building blocks of hair.

“People who have anorexia nervosa or chronic diseases where they might not be getting enough protein and nutrients typically have thinning hair,” she says, adding that the DRI (Dietary Reference Intake) for protein set by the National Academy of Science is .8 grams of protein per kilogram of body weight (for example, a 120-pound woman would need 45 grams a day, and a 180-pound man would require about 65 grams daily).

“On average, people meet or exceed their daily requirement, because a lot of foods we typically eat contain [protein],” she says, except for pure fats like oils, butter, margarine, or fruit. Most other foods contain varying amounts.

“A slice of whole-wheat bread has three grams and three ounces of ground beef has about 30 grams,” she says. “While animal sources have higher amounts, many vegetables contain small amounts, even potatoes,” she says, adding that children raised on a vegan diet also are at risk because they need a significant protein intake for growth.

Cohen explains while incorporating more protein into the diet doesn’t necessarily increase hair health, a nutrition deficiency will have an effect on both hair and skin.

“While not often determined by bloodwork, a registered dietitian can do a nutrition-focused physical exam to help evaluate protein and nutritional status by assessing one’s body, hair, nails, skin, diet, and lean body mass,” she says. “When in doubt, get checked out by a professional.”

While nutrient deficiencies can be revealed in hair quality or shown through hair loss, there are other factors that can trigger a change. Stress can produce an increase in the stress hormone cortisol, which can shock many systems of the body, including the hair growth cycle. Shifts in estrogen can do the same.

“When a woman’s pregnant she produces more estrogen, which helps hair grow faster. However, after giving birth she produces less of it and sheds this increased growth,” Cohen says, adding that hair loss is common in menopause since less estrogen is being produced.

But factors aside from hormones affect our hair as well.

Cohen says that genetics play a role in male pattern baldness. Medical conditions, climate, medications, smoking, and the natural process of aging impact our hair, too.

“As people get older, there’s different active growth stages of hair that make it grow slower and you grow less hair, which makes it thinner,” she says, adding that age affects its color as well.

Melanin, a natural substance produced in our body, is responsible for the color in our skin and eyes as well as our hair.

“The amount of melanin in our bodies is determined by our genes,” says Alixandra Crompton, outpatient registered dietitian at Robert Wood Johnson Barnabas Health at Jersey City Medical Center. “Those with a lot of melanin have dark hair, and those with less have lighter,” she says, noting that redheads have a different type of melanin altogether called pheomelanin.

Crompton explains that melanin reduces naturally as we age, turning our hair gray or white.

“There’s little muscles on our head that connect to the follicle, and that muscle lifts our hair to regulate heat and temperature,” she says. “When it lifts up it traps air inside, and as more air gets trapped over time, the more melanin we lose, and the more gray we get. Texture, thickness, and length also depend on genetics, and everyone’s hair has a different life cycle. The longer the growth phase, the longer the hair. “It truly depends on the person. One’s hair life cycle can range from two to six years,” she says.

While hair has a lot going on below the surface, there are some things to pay attention to.

Crompton explains that shedding is normal, and losing between 70 and 100 hairs a day should be of little concern. If larger clumps fall out from light touching or brushing, one should talk to a professional. “This is more often seen in people undergoing chemotherapy or having adverse reactions to medications,” she says. “Thinning hair can also be a sign of malnutrition.”

Supporting Hair Health

Crompton says sticking to a well-balanced diet is the key to keeping our bodies—and hair—the healthiest they can be. While protein is an important part of it, certain vitamins and minerals are also beneficial.

“B vitamins encourage cell rejuvenation and can help support hair follicles and can be found in foods like fish, whole grains, and dark leafy greens,” she says, adding that foods high in antioxidants support hair health as well. “Vitamin A, C, D, and omega-3 fatty acids help fight against free radicals, which are molecules that can damage cells, cause illness and be detrimental to our bodies,” she says. “They form naturally and can be caused by stress, drugs, alcohol, and the intake of processed foods. These nutrients help prevent the formation of free radicals which can also be harmful to hair, in addition to aiding in disease and cancer growth.”

“A REGISTERED DIETITIAN CAN DO A NUTRITION-FOCUSED PHYSICAL EXAM TO HELP EVALUATE PROTEIN AND NUTRITIONAL STATUS BY ASSESSING ONE’S BODY, HAIR, NAILS, SKIN, DIET, AND LEAN BODY MASS.”

Other nutrients like zinc and iron can benefit hair as well.

“The exact mechanism of action between zinc and hair health is not completely understood, however, zinc is an essential mineral, meaning that we can only obtain it through foods and supplements and it is not produced naturally by our body,” she notes, adding that zinc is involved in many aspects of cell growth and plays a role in protein synthesis and cell division among others. Zinc can be found in foods like beef, oysters, lentils, and spinach.

“Iron is important too, because a deficiency can lead to health issues including hair loss (as well as fatigue weakness) common for those who follow plant-based diets,” says Crompton.

“Iron helps produce hemoglobin, which is a protein found in our red blood cells. Hemoglobin is known to deliver oxygen to our cells to help them divide and repair, including those [cells] involved in hair growth,” she says, noting iron can be found in both animal products as well as plants like dark leafy greens or fortified foods. Consuming it alongside vitamin C aids in absorption.

While still being studied for its effects on hair, biotin is another B vitamin that helps the body metabolize protein and is found abundantly in eggs, specifically the yolk. It’s also often found in hair supplements, which Crompton says to be wary of.

“Be cautious of hair supplements. Some have a lot more of a specific nutrient than our bodies need. There’s too much of a good thing. For example, vitamin A is really good for your hair, but if you have too much, it can actually cause hair loss,” she says. “Supplements are just that—your body prefers getting nutrients from food, so consider taking a general multivitamin rather than indulging in specific hair vitamins or popular hair gummies,” says Compton, which are oftentimes much more expensive.

“If you do have a nutrient deficiency, your body is good at letting you know,” she says. “It’s important to remember that you’re your own best barometer.”

POSSIBLE NUTRITION-RELATED CAUSES OF HAIR LOSS OR CHANGES

Courtesy of Alixandra Crompton, outpatient registered dietitian, Robert Wood Johnson Barnabas Health at Jersey City Medical Center

Thin, sparse, and patchy hair could be caused by deficiency of:

• Iron: meat, fish, poultry, enriched and fortified grains
  **Take with vitamin C sources to improve absorption
• Zinc: meat, poultry, fortified breakfast cereals, beans, nuts, whole grains
• Protein: whole grains, eggs, meat, poultry, fish, seafood, nuts, seeds, tofu, soybeans, cheese, milk, yogurt

Color changes, depigmentation, lackluster hair could be caused by deficiency of:

• Manganese: whole grains, clams, oysters, mussels, nuts, soybeans and other legumes, rice, leafy vegetables, coffee, tea, and spices such as black pepper **Drinking water also contains small amounts
• Selenium: seafood, meat, poultry, eggs, dairy products, breads, cereals, and other grains
• Copper: shellfish, seeds and nuts, organ meats, wheat-bran cereals, whole-grain products, and chocolate

New corkscrew hairs could be caused by deficiency of:

• Vitamin C: citrus fruits, tomatoes, potatoes, red and green peppers, kiwi fruit, broccoli, strawberries, Brussels sprouts, cantaloupe, and fortified breakfast cereals
  **Best to consume raw when possible as cooking and prolonged storage can reduce vitamin C content

ADDITIONAL HAIR PROTECTION TIPS

Courtesy of Deborah Cohen, associate professor of clinical and preventive nutrition science, Rutgers University School of Health Professions in Newark

• Wear a hat to protect from sun
• Avoid chemicals in hair products and chlorinated pools (or rinse chlorine out of hair afterwards)
• Limit using heat styling hair tools
• Be sure you’re getting enough protein in your diet.
• Don’t go on extreme diets like a low calorie (low protein) diet
• Be careful with supplements. There’s not a lot of research that they work. Go for a good-quality multivitamin and keep up with a balanced, whole-foods diet