The best method of diagnosing whether the hair loss is due to diabetes is through elimination and differential diagnosis. Hair fall can be hereditary, due to lack of nutrition, as a side effect of medicine etc. The process of elimination will enable us to know for certain whether the cause behind hair loss is diabetes.
Blood sugar level: The blood of a diabetic person does not have a balanced sugar level, so the blood does not reach the hair follicles or the roots of the hair. Therefore, the pores of the hair are severely under-nourished. It does not receive the nutrients it requires which are brought by the natural blood flow. The roots get weaker and hair stops growing. It cannot develop and renew itself, and this is the case in hyperglycemia.
Another important factor is that the healing and rejuvenation time in diabetics is comparatively slower than in normal individuals. This leads to significant hair reduction, as diabetics cannot maintain the average cycle of hair regrowth.
Hair loss during diabetes is sometimes attributed to telogen effluvium. All hair has a growth phase, called anagen, and a resting phase, called telogen. In normal people, at any given time, 5-15% of the hair on the scalp is in telogen phase. Telogen effluvium is a condition triggered when a physiologic stress or hormonal change like diabetes causes a large number of hair to enter telogen at one time leading to diffused hair shedding.
Circulation Problems: High blood sugar can chemically react with red blood cells, creating a product known as glycosylated hemoglobin. Hemoglobin is an important protein in red blood cells and this modified version causes red blood cells to be misshapen. These misshapen red blood cells are not as flexible and can get stuck when trying to enter small blood vessels (called capillaries), leading to circulation problems. If this occurs in the capillaries that supply blood to the hair follicles, these follicles may die, leading to hair loss. So it all boils down to poor circulation.Endocrine Abnormalities: Another way in which diabetes can cause hair loss is by disrupting the endocrine system. The endocrine system is comprised of many hormones that control different tissues in the body. For example, the endocrine system secretes androgens of which govern hair growth and the health of hair follicles. Uncontrolled diabetes (and resulting high blood sugar) causes the endocrine system to become disrupted. This can lead to androgen (Growth) abnormalities, which can cause the hair follicles to go dormant. As a result, the shafts of the hair fall out, which can lead to widespread hair loss. Fortunately, if the diabetes is controlled (through diet and medication and or supplementation), the hormone levels can become stabilized, allowing the hair to grow back. The flip side is that some of the same drugs may cause the initial hair loss so it can be an extremely painful balancing act.