Woman eating a cake by a window

How low magnesium affects your blood sugar

If you always crave something sweet at 3pm, you could have low magnesium levels. Here’s how the mineral works to maintain healthy blood sugar.

We tend to think of magnesium as a stress reliever – it’s found in Epsom bath salts to soothe tired muscles – but studies show it also plays an important role in keeping our blood sugar levels steady too.

So how does magnesium help support a healthy blood sugar balance, and beat those mid-afternoon cake cravings?

What is blood sugar?

When we eat, food makes its way through the stomach and intestines, and is converted into glucose or blood sugar, our bodies’ fuel. In response, the pancreas pumps out insulin – a hormone that helps your cells absorb glucose for energy – and your blood sugar levels start to fall.

But if you eat a big starchy meal with lots of white carbohydrates or sugar, such as cake or white pasta, the body receives too much glucose and responds by releasing increased amounts of insulin.

This brings your blood sugar levels down, but by far too much. Symptoms of low blood sugar – called hypoglycaemia – include:
• feeling cloudy headed
• tired or a lack of energy
• hungry
• shaky and weak
• nauseous
• dizzy

If this keeps happening over time, your body could stop responding to the insulin it makes (called insulin resistance) or stop producing insulin altogether, leading to diabetes.

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What does magnesium do?

Magnesium plays an important role in helping your body convert glucose from your food into fuel. If you don’t have enough magnesium in your body, your cells can become less effective at using insulin.

In fact, a 2003 study of 219 women published in the Journal of the American College of Nutrition found that those with higher magnesium intakes had lower fasting insulin levels.1 This means that they were more sensitive to the insulin in their bodies, so their blood sugar levels were more stable. A later study of 234 people by the Medical School of Yangzhou University, China, in 2013 concluded that ‘increasing dietary magnesium to meet the RDA has a protective effect on insulin resistance’.2 So how much magnesium do we need? The recommended daily amount (RDA) is 270mg for women and 300mg for men3 but studies show we’re not eating enough magnesium to benefit from its effects.4

How to balance your blood sugar

Nutrition experts recommend eating green leafy vegetables such as spinach, nuts, brown rice, dairy products and wholegrain foods to naturally increase your magnesium levels.

Following some simple tips can also help maintain healthy blood sugar levels:
• eat regularly, at the same times every day

• don’t skip meals – research by Cornell University found meal-skippers bought 31% more junk food while food shopping later that day5

• eat balanced meals, with a good mix of protein, fats and carbohydrates to help avoid ‘sugar crashes’

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Advice is for information only and should not replace medical care. Please consult a doctor or healthcare professional before trying any remedies.
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1. Fung TT, et al. The association between magnesium intake and fasting insulin concentration in healthy middle-aged women. Available from: https://www.ncbi.nlm.nih.gov/pubmed/14684759
2. Wang J, et al. Dietary magnesium intake improves insulin resistance among non-diabetic individuals with metabolic syndrome participating in a dietary trial. Available from: https://www.ncbi.nlm.nih.gov/pubmed/24084051
3. NHS Choices. Vitamins and minerals. Available from: https://www.nhs.uk/conditions/vitamins-and-minerals/others/#magnesium
4. Gröber U, Schmidt J, Kisters K. Magnesium in Prevention and Therapy. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4586582/
5. Stacey Shackford. Don't shop hungry, pre-order lunch to make healthier choices. Available from: http://news.cornell.edu/stories/2013/05/grocery-shopping-when-hungry-can-be-fattening