If your hair has started thinning or falling out, age might not be the main reason. What you eat and drink could be a bigger factor than you think.
New research, published in the journal Nutrition and Health, reviewed 17 studies to explore how diet affects hair. The findings show that certain foods and drinks can contribute to hair loss, while others can actually help your hair grow stronger and thicker.
Drinking sugar-sweetened beverages and alcohol has been linked to a higher risk of losing hair. Laura Acosta, a registered dietitian and associate professor at the University of Florida, says that too much sugar causes insulin spikes that trigger inflammation, which can disrupt your natural hair growth cycle.
Alcohol, while not directly causing hair to fall out, can cause your body to absorb fewer nutrients. It can also put stress on the liver, disturb sleep, and increase inflammation in the body—all of which can negatively impact hair growth.
Lack of protein is another major cause of hair loss. Acosta recommends getting at least half a gram of protein per pound of body weight daily. Many people don’t realize they’re not getting enough. Dr. Jila Senemar, a menopause specialist in Miami, adds that hormones, diet, and hair shedding are closely linked.
On the brighter side, some foods can help support hair health. Soy-based foods like tofu and edamame, and vegetables like broccoli and cauliflower (called cruciferous veggies), are good choices. These foods are high in natural plant chemicals with antioxidant and anti-inflammatory benefits.
Another option is persimmon leaf, which may help improve hair density and thickness. It can be consumed as a tea or supplement and contains compounds like quercetin that may boost blood flow to the scalp.
The studies also looked at supplements. One study of 76 men with male pattern baldness found that those who took 400 mg of pumpkin seed oil daily for 24 weeks had more hair growth compared to those who took a placebo. Researchers believe the pumpkin seed oil may reduce levels of a hormone called DHT, which is linked to hair loss.
Vitamin D stood out as one of the most studied supplements in the review. At least five studies found that people with higher vitamin D levels had less hair loss. Acosta recommends 2,000 IUs a day but warns that too much can be harmful.
Iron is another important nutrient. One study showed that women who took 100 mg of iron had better hair growth. Dr. Senemar says people who are low in iron should take it with vitamin C to help with absorption. Foods like spinach, lentils, and almonds are also good sources of iron.
Acosta also advises checking levels of zinc and biotin (Vitamin B7), since low levels can cause hair thinning. Adults need about 30 micrograms of biotin daily. Good sources include meat, eggs, fish, nuts, seeds, and sweet potatoes. However, she warns that if you’re not deficient, taking more biotin is unlikely to help.
Finally, collagen is gaining attention. Acosta notes that although she was once skeptical, recent research on collagen supplements for hair growth looks promising.
The new review studied over 613,000 people from ages 7 to 77 across three major scientific databases. Most participants were women. While these studies were observational—meaning they found links but not direct proof—they offer valuable insights into how diet may impact hair health.
The study is published in Nutrition and Health.
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