Several research programs for studying and establishing hair trace mineral concentrations have been implemented since 1965 by the International Atomic Energy Agency. These research programs have been coordinated under “Nuclear-based Methods for the Analysis of Pollutants in Human Hair.” Hair was chosen by the I.A.E.A. due to the concentration of minerals in the hair and its reflection of both external and internal contamination. The bulk of data on trace element concentrations has been reported from hair samples obtained from the scalp.

Bioassay of hair is attractive as it is an effective bio-concentrator, samples can be easily stored, the concentration reflects an integrated value, and, finally, the measurement of the (234)U/(238)U isotopic ratio in digested hair samples by MC-ICPMS is feasible and highly informative.

Coronary calcification scores were strongly associated with a higher calcium­to­magnesium ratio in the hair than lower calcium to magnesium ratios found.

Hair samples were sent to Trace Elements, Inc, (TEI), via TEI­Korea. Zinc deficiency was found in the hair of eighty­eight percent of the study group. Serum zinc was found low in fifty­five percent of the affected group. Zinc therapy resulted in improvement in clinical signs and symptoms in most of the children including increase in body weight, appetite and growth.

Findings reported that individuals with normal serum testosterone levels had a significantly higher HTMA zinc level compared to a low testosterone group. Also, the study concluded that decreased testosterone was associated with a significant reduction of the zinc to copper ratio in hair samples.

Various mineral imbalances as revealed by hair analysis can indicate metabolic dysfunctions before any symptoms occur, and that hair analysis of minerals is used not only for diagnostic purpose but also to monitor the nutritional state of the patient until treatment benefits are achieved and the effects of the program have been stabilized.

The value of exposure (kinetics and dose) of orthodontic patients to metal ions released from orthodontic appliances can be assessed by hair mineral analysis.

Human head hair is a recording filament that can reflect metabolic changes of many elements over long periods of time and thus furnish a print-out of post nutritional events.

It is well known that nutritional mineral deficiency can impair neurological development. Some transitional nutrients can cause later-life health disturbances when deficient in the diet, but in excess can be just as harmful and include iron, copper, manganese, zinc and others. Heavy metals such as lead, cadmium, mercury and arsenic are also neurotoxins and when present early in life can contribute to impaired neuro-development and detrimental health effects later in life and have been called the “fetal origins of disease.” Hair concentrations of cadmium compared to reference groups were found to be higher in children with mental retardation, learning disabilities, dyslexia and lower I.Q.

Multivariate apportionment of trace elements in the blood, scalp hair and nails of the patients was also significantly different than that in the healthy donors.

Hair, blood and urine minerals analyzed in diabetic patients compared to non-diabetic controls showed that the mean levels of zinc, manganese and chromium were significantly lower in the blood and scalp hair of patients diagnosed with diabetes. Higher levels of copper and iron were also found in the scalp hair of the diabetic group as well.

The consequence of trace elements deficiency has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality.

Statistical evaluation of these data by multivariant analysis (MANOVA) using a contrast matrix and by discriminant analysis showed that elemental hair anomalies can be used to diagnose correctly the above-mentioned pathologies, demonstrating the usefulness of hair analysis as a complementary tool for the detection of disturbances in calcium/bone metabolism.

The consensus of most workers in the field is that if hair samples are collected properly, cleaned and prepared for analysis correctly and analyzed by the best analytical methods, using standards and blanks as required, in a clean and reliable laboratory, by experienced personnel, the data are reliable.

The high exposure of toxic elements may be synergistic with risk factors associated with hypertension. These data present guidance to clinicians and other professionals who will be investigating the toxicity of heavy elements in biological samples (scalp hair and blood) of hypertensive patients.

Higher values of scalp hair mercury and lead content were observed in men and women with increased body mass index independently of their age.

Results showed twice the level of lead in the malnourished group compared to the control group and half the levels of calcium, iron and zinc.

Their findings show that adverse health effects of individuals living near or in a polluted environment is not only associated with heavy metals exposure, but altered mineral homeostasis as well.

Hair samples were analyzed in fifty women along with their coronary calcium scores, bone mineral density. They found that coronary calcium scores were negatively correlated with bone mineral density and hair calcium levels.

Hair and dental tests showed higher levels of lead, mercury and tin in tissues obtained from groups living in polluted areas. Therefore, hair and dental material can be used as indicators of environmental pollution.

Hair zinc levels and serum iron levels decreased significantly toward the end of the first year. The maternal hair copper and serum iron also decreased. The study concluded that infants appear to require an increase in zinc intake after six months of age.

Both hair and serum minerals were analyzed as well as serum insulin, HbA1c, glucose, and cholesterol. The patients with diabetes had higher hair iron and lower serum zinc than controls. Insulin levels were positively associated with the hair copper / zinc ratio.

Findings included lower tissue levels of zinc, copper and chromium in the diabetic group and these levels were significantly lower with higher HbA1c levels.

Lower hair copper was correlated with higher body mass index, waist circumference, blood pressure, and low HDL. Individuals with NAFLD had significantly lower hair copper levels.

Findings concluded that 1 to 2 year old children with Down’s syndrome are characterized by significant alterations of mineral and trace elements status.

Hair samples were analyzed in a group of individuals with orthodontic appliances after one year since placed. Elevated levels of both nickel and chromium were found in the treatment group compared to controls.

A study of men over a period of thirteen years found that for each microgram of mercury found in the hair, the risk of acute coronary events increased by an average of eleven percent and cardiovascular disease death rate by ten percent.

An example of how mineral intake is reflected in the hair was demonstrated in a study of several thousand Iraqi peasants, whose diet contained grain heavily treated with fungicides. The fungicides contained organic mercury, which was reflected in higher concentrations in the hair when consumption was highest and decreased when consumption was lowest. Hair concentrations correlated directly with the extent of symptoms.

Hair samples collected and analyzed from five countries with known arsenic sources, both high and low included the United States, Canada, and People’s Republic of China, Bangladesh and Nepal. Hair arsenic concentration in all hair samples correlated with the amount of arsenic in drinking water and revealed the low intake of selenium in areas of high arsenic concentrations. The results demonstrate the viability of hair as a noninvasive biomonitor in assessing aspects of dietary Se and environmental As exposure.

The proliferation of trace element analysis as a tool for biological investigation of nutrition, growth and development, and disease processes has led to consideration of (hair) trace element analysis as a means not only of present evaluation and estimation, but also as a technique for the reconstruction of past biological events in an organism.

The findings indicate that hair samples are superior to urine samples. Even so, it can provide more valuable information for prevention, diagnostics, treatment and research of diabetes by simultaneously analyzing the hair and urine samples.

Older pregnant women had lower hair zinc, vanadium and cadmium content and higher boron compared to younger women. Their data indicates that lifestyle factors has an influence on age-related changes in hair trace elements during pregnancy that may impact the outcome of pregnancy.

The children of the IVF group had low hair levels of chromium, iron, magnesium and higher mercury and molybdenum compared to the control group. Hair mineral levels were associated with infertility and pregnancy complications. The authors conclude that the results suggest the need for preconception monitoring and correction of essential elements as well as toxic metals in order to improve the course of pregnancy and child development.

Copper to zinc and phosphorus to zinc ratios were found to be significantly lower in affected children than controls. Apparently elevated higher hair zinc levels were correlated with more symptoms of inattention, hyperactivity and total ADHD symptoms.

Lower levels of these elements was associated an increase presence of hypertension and reflected the different dietary intake between the two groups tested.