"Cortisol is one of the main hormones produced by the adrenal glands. Cortisol plays a key role in the regulation of blood Sugar levels. Stressful conditions, however, cause the adrenals to overproduce cortisol, and when the adrenals are pushed into a relentless production of cortisol, they end up in a stressed condition. Once the adrenals become overworked and stressed, the body's ability to retain magnesium drops down, as reflected in a greater loss of magnesium through urinary excretion. For this reason, people with exhausted adrenals will often require more magnesium to maintain inner balance. Magnesium is also needed by the adrenals as a basic building block for the manufacturing of hormones.
Since stressed adrenals are often a forerunner of Depression and mood disorders, anything which supports adrenal function will help these conditions. Because magnesium supports adrenal function, it can and was indeed found to have an antidepressant effect. While further steps may be required to fully alleviate depressive states, magnesium's role in balancing the body is vital and it has been proven to greatly enhance the effect of other nutrients consumed and/or other steps undertaken.
Without sufficient magnesium one cannot keep the adrenals in balance, and a loss of this balance can result in diabetes, hyper-excitability, nervousness, mental confusion and difficulty coping with simple day-to-day problems. Depressed and suicidal people often display inadequate levels of magnesium."