RDA is 270 mg for women and 300 mg for men (the World Health Organisation recommends 400 to 450 mg a day).
Magnesium is a macro-mineral that is very important to good health. Around 80% of all the enzymes in your body need magnesium.
Where do you get magnesium from?
Magnesium is found in seeds, whole grains, almonds, walnuts, green vegetables and pulses.
It is essential for releasing energy from food; it is vital in making proteins for proper growth and development; has a role in producing insulin and maintaining the health of heart, blood vessels and nerves; it may protect against cancer.
It is necessary for producing neurotransmitters in the brain and is in the enzyme that metabolises essential fatty acids.
Too much magnesium
Excess magnesium is almost unknown as the body rapidly removes it. If calcium is low, too much magnesium can cause muscle weakness and fatigue.
Too little magnesium
Too much calcium causes magnesium levels to fall, as do alcohol, diuretics and the contraceptive pill.
Lack of magnesium causes muscle tics and tremors, anxiety and depression.
Low magnesium levels are implicated in many diseases, such as high blood pressure, migraine, multiple sclerosis, glaucoma, osteoporosis, lack of energy, female hormone disorders and diabetes, but whether that is a cause or a result is open to debate
Supplements should have calcium as well as magnesium as there needs to be a balance with calcium for proper absorption.