HealthSpan Wellness

Julia Fountain ND MSCP

As you read this, 90% of the hair on your head is growing and 10% is sitting pretty. Healthy hair grows for 4-6 years, then enters a resting phase of 2-3 months before being shed. Most people shed about 100 hairs per day. Once a hair is shed a new hair from the same follicle replaces it. New hair grows at a rate of approximately ½ inch per month. If your hair isn’t measuring up, consider some of these factors…


Nutrient depletion is the most common cause of hair loss in women before menopause. Iron depletion is the first to consider and this is diagnosed based on iron stores (ferritin levels) in the blood. Ferritin levels above 80 mmol/L are associated with healthier hair.

Cells of hair follicles have a high turnover rate and have a high need for energy and nutrients.

Deficiencies of protein, Vitamin D, Omega 3 fatty acids, B vitamins and minerals such as zinc and silica can contribute to more hair shedding. Biotin is the most popular ‘hair vitamin’, however to date there are no high quality human studies on the use of biotin in hair loss. If you’ve tried biotin for hair loss with no benefit, biotin deficiency is not the cause.

Nutrient deficiencies can be a result of poor diet, chronic dieting, poor absorption, intestinal disease, illness, or an active lifestyle without nutrition keeping pace (underfueling).

The good news – when deficiencies are corrected and diet improved, the hair will grow back.

Hormone changes

Hormone changes are the most common cause of hair loss in women after menopause. A decline in estrogen and progesterone during peri and post-menopause results in a relative excess of testosterone and its derivative, dihydrotestosterone (DHT). DHT shortens the hair hair growth phase and shrinks the hair follicles.

Estrogen is thought to protect against hair loss, however estrogen hormone therapy does not consistently promote hair growth in postmenopausal women. Instead, treatments are aimed at blocking production of DHT.

Hair loss can also be a symptom of thyroid disease and polycystic ovary syndrome (PCOS) in women.

During pregnancy a large percentage of hair follicles are in the growth phase and shedding is less. After a woman gives birth a large number of follicles shed hair at once. Hair typically returns to its normal fullness and growth cycle within a few months. If not, investigating nutritional and hormone status can be helpful.


Aging leads to reduced hair density and thinner fibers which can feel like hair loss.

Cardiometabolic factors

Conditions such as high blood pressure and diabetes affect microcirculation to the scalp which can affect health of the hair follicle.


Severe or prolonged physical or emotional stress pushes large numbers of growing hairs into a resting phase. It may take 2-3 months after the stressful event for the hair to fall out. The hair typically grows back with the emotional or physical stress is resolved, though it may take 6-9 months.


The immune system activates and white blood cells attack the hair follicle. This is known as alopecia areata. Within weeks the affected hair falls out. Alopecia starts with small patches and may progress to other areas of the scalp.

Medication side effects

Some women notice hair loss after starting a new medication such as blood thinners or beta-blockers. The hair loss in this case may not be immediate but could appear 2-3 months after starting a new medication.

Environmental factors

Microinflammation of the hair follicles can occur with scalp sunburn, smoking, environmental pollutants (including chemicals in hair care products and treatments), and scalp infections (usually fungal). When the cause of scalp inflammation is resolved, the hair grows back.


Female-pattern hair loss is genetic and usually starts with a widening through the center hair part. The hair loss rarely progresses to baldness as it might in men. These women may be genetically more sensitive to the effects of DHT.

Getting to the root of the problem

Treating hair loss demands getting to the root of the problem. Some of these factors are diagnosed through labwork and treated by making adjustments to routines, optimizing nutrition or taking supplements and others will require medical evaluation and intervention.