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No one wants limp, dull, or brittle strands, these are all telltale signs of unhealthy hair. Just like skin and nails, what we consume or inflict on our bodies can affect our hair and scalp. They are all related so no matter what miracle hair care products you buy, if your body is unhealthy then it will show in your hair.
if your body is unhealthy then it will show in your hair
Jessica

Just as dermatologist Jessica Wu says, “Both are a barometer of how well (or how poorly) you're feeding the body as well as your overall health." You are what you eat and eating poorly affects your entire body including your hair. Food is not the only defining factor for healthy hair as diet, exercise, and mental well-being is just as crucial in the equation for strong and luscious strands. Here are five things you really need to avoid to have and keep healthy hair.

Crash dieting

Crash dieting gives the body a shock and the human body is designed to react to that shock by compensating in some way. Crash diets often deprive the body of vital nutrients and it is not going to just sit around waiting for them. Without those nutrients in the blood stream to feed hair follicles the strands become starved and may become lifeless, brittle and in some cases begins to fall out or break. This is how excessive shedding can be related to the stress of caloric restriction or the crash diet.

Heat styling

We stress the importance of limiting your heat styling because heat tools can actually burn the hair and cause irreversible damage. Always use a heat protectant and try not to use heat tools too often (weekly is considered often).

Stressing

According to Dr. Daniel K. Hall-Flavin, stress and hair loss are related. When I get stressed my face breaks out and I get headaches but any kind of physical trauma, whether it is a car accident, surgery, or a serious illness can cause temporary hair loss called telogen effluvium. There are two other types of stress related hair loss called alopecia areata (the immune system turns on the hair follicles and causes hair to fall out) and trichotillomania (a person compulsively pulls out their own hair). 

Stress can actually shock the hair cycle into the shedding phase and can become noticeable three to six months after the trauma. The hair will grow back once the stress is removed and while some stressors we cannot avoid, many others can and should be avoided but be patient as once the stressor had been removed it will take time for the shedding to stop. I often notice months later after a stressful period that the shedding increases but eventually slows down so when I am under stress I up my tea rinses and try to relax more.