Kidney failure, alcohol consumption and absorption issues (Magnesium is absorbed in the small intestine and colon) also effect magnesium levels. Thus, individuals with intestinal or colon damage such as Crohn’s disease, irritable bowel syndrome, coeliac disease, gastroenteritis, idiopathic steatorrhoea, ulcerative colitis, resection of the small intestine, ileostomy patients or patients with ulcerative colitis may have magnesium deficiency.
For many of Susan’s clients they show symptoms of magnesium deficiency, unfortunately because serum magnesium does not reflect intracellular magnesium, the latter making up more than 99% of total body magnesium, most cases of magnesium deficiency are undiagnosed. In developed countries it has been found that just over 24% of youth have insufficient magnesium in their diets. The RDA for magnesium is between 300mg – 420mg per day. It is estimated that less than 50% of Americans hit the recommended daily amount. Magnesium deficiency has been found in 84% of postmenopausal women with osteoporosis.
Since 1940 there has been a tremendous decline in the micronutrient density of foods. In the UK for example, there has been loss of magnesium in beef (−4 to −8%), bacon (−18%), chicken (−4%), cheddar cheese (−38%), parmesan cheese (−70%), whole milk (−21%) and vegetables (−24%).The loss of magnesium during food refining/processing is significant: white flour (−82%), polished rice (−83%), starch (−97%) and white sugar (−99%).
Increased calcium and phosphorus (cola in particular is a large source of some individuals phosphorus intake) intake also increases magnesium requirements and may worsen or precipitate magnesium deficiency.
A common misconception is that consuming phytate-rich foods can lead to nutrient deficiencies particularly magnesium depletion via binding by phytic acid. However, urinary magnesium excretion will drop to compensate for a reduction in bioavailable magnesium. And most high-phytate foods are also good sources of magnesium (grains and beans are good examples). Thus, it is unlikely that consuming foods high in phytate will lead to magnesium depletion. However, a vitamin B6-deficient diet can lead to a negative magnesium balance via increased magnesium excretion.
The reasons for magnesium deficiency are varied, some are dietary and since most vitamins and minerals work in synergy with each other they all must be balanced,
supplementing with calcium can lead to magnesium deficiency due to competitive inhibition for absorption and over supplementing with vitamin D may lead to magnesium deficiency via excessive calcium absorption. Use of diuretics and other medications can also lead to magnesium deficiency.
So what are the best dietary sources:-
Unrefriend Whole grains
Dietary sources are always the optimal way of obtaining your nutrients.
Reference : https://openheart.bmj.com/content/5/1/e000668