1. Sugary Drinks
Sugary drinks can sabotage hair health by contributing to inflammation and hormonal imbalances that interfere with the hair growth cycle. According to Dr. Kanwal, “Very sugary drinks and desserts can worsen hair thinning by spiking insulin and inflammation, which may move more follicles into a shedding phase and worsen hormonal acne and scalp oiliness in some people.” Over time, these repeated blood sugar spikes can stress the body and scalp, making hair more prone to thinning and excessive shedding.
2. Deep Fried Foods
Deep fried and fast foods often lack the nutrients hair needs while causing inflammation that can weaken follicles. Dr. Kanwal explains, “Fast food and deep fried foods are often high in saturated fat and poor in vitamins, which can promote low grade inflammation and crowd out the protein, iron, and micronutrients hair needs to grow well.” When these foods take up too much space in the diet, they can take the place of healthier options that support stronger, thicker hair growth.
3. Refined Carbs
Refined carbohydrates like white bread, pastries, and chips may be convenient and tasty, but they offer little nutritional value for hair health. Dr. Kanwal notes, “Highly processed refined carbs like white bread, pastries, and chips behave similarly to sugar, giving quick blood sugar swings that may aggravate hormonal changes linked with shedding in susceptible people.” These fluctuations can disrupt the hair growth cycle, especially for those already dealing with hormone-related thinning.
4. Fish High in Mercury
While fish is often praised for its health benefits, certain types can be harmful to hair when eaten too frequently. Dr. Kanwal cautions, “Very high mercury fish, such as large predatory fish eaten often, can be a problem because excess mercury is linked to hair loss and can displace other minerals that are important for healthy follicles.” Overexposure to mercury can interfere with nutrient balance in the body, weakening hair at the root.
5. Low Protein Diets
Protein is a critical building block for hair, and not getting enough can quickly show up as shedding and slow regrowth. “Extreme low protein diets or regularly skipping protein rich foods like eggs, beans, dairy, or lean meats force the body to ration amino acids, and hair is one of the first tissues to show the effect with increased shedding and slow regrowth," Dr. Kanwal says. Without adequate protein, the body prioritizes vital organs over hair production.
6. Alcohol
Alcohol can affect hair health indirectly by disrupting several systems the body relies on for growth and repair. “Heavy alcohol intake can indirectly worsen hair health by disturbing sleep, increasing inflammation, and reducing absorption of key nutrients like B vitamins and zinc, so over time the hair looks thinner, drier, and more breakable,” Dr. Kanwal says. When consumed in excess, alcohol can leave hair weaker, duller, and more prone to damage.