Can dietary magnesium improve insulin resistance?
Evidence suggests yes.
But this does not mean everyone needs to run out and buy magnesium supplements (actually the opposite).
It’s always a better idea to first assess your daily intake of magnesium rich foods to understand if you are eating enough to meet your requirements (with or without insulin resistance).
Because adding additional supplementation when dietary magnesium is ok, can cause gastrointestinal side effects amongst other things. So always discuss any supplements with your GP or dietitian first.
What is insulin resistance
Insulin resistance is a metabolic condition which occurs when there is a fractured relationship between the action of the hormone insulin and cell receptors on muscle tissue.
Insulin is the hormone responsible for transporting glucose -ie: sugar molecule units or carbohydrates- from the blood into the cells where it used in energy metabolism.
In insulin resistance, sugar goes not move into the cell leading to high blood glucose levels. The body responds to this, by making more insulin, leading to high blood insulin levels.
Excess insulin (hyperinsulinemia) can have many negative outcomes for our health. For prenatal, pregnancy, PCOS, fertility and so forth, excess insulin shifts sex-hormone balance, impacting ovulation. It can lead metabolic syndrome, alter how the body stores weight and a whole host of other physiological pathway changes.
So what can we do? As a dietitian I look at your whole diet, micronutrient and macronutrient intake/deficiencies, lifestyle, goals, diet, history, family history, health history and so forth to find the perfect carbohydrate threshold for you (it is different for everyone). I teach meal balance, and supplement as required. And I look at dietary magnesium intake.
Magnesium and insulin resistance
Magnesium is a mineral utilised by the body for a variety of metabolic pathways. This includes glucose/sugar metabolism, or energy production.
Several studies have looked at the relationship between magnesium supplementation, insulin and blood glucose parameters, ie: did magnesium supplementation improve fasting insulin or blood glucose levels. The results from a systematic review of randomised controlled studies looked at exactly this – and the results were mixed. But this was attributed to, by the authors, the variation in the research -types of magnesium and dose used, the study population, data collection methods and so forth.
But when you step back at look at the data, there is an overwhelming trajectory toward reduced fasting insulin levels when people who were low in magnesium at baseline corrected their deficiency.
So supplement or not, it absolutely will do no harm to ensure you eating enough magnesium rich foods every day if you have insulin resistance (and if you don’t have insulin resistance).
I will give you some dietary guidance in this article, but this general only. It’s not individual. If you want to get a better picture of what magnesium adequacy looks like for you, book a 1:1 consultation and we will cover it all.
Foods rich in magnesium
Magnesium is one of those nutrients I pay attention to, but I find not many clients do (unless they experience sleeplessness or leg cramps). And it it can be tricky to meet your requirements without some dietary planning.
Pumpkin seeds, almonds, legumes, leafy greens like spinach and chard, sesame seeds, quinoa, soybeans, oats, sunflower seeds, seaweed, salmon, flaxseeds, brazil nuts and tofu (to name a few) are decent sources. But you need to consume several of these foods every day to meet your needs.
To give you an idea, these are the current (at time of writing) Australian nutrient recommendations for women, pregnant people and those breastfeeding:
Women aged 19-70 years
310-320mg/day
On a plate:
- 28g pumpkin seeds
- 1 cup cooked spinach
- 1 avocado
- 1/2 cup oats
Pregnancy
350-400mg/day
On a plate:
- 1/2 cup tofu
- 28g sesame seeds
- 28g flax seeds
- 28g cashews
- 2 slices whole grain bread
Breastfeeding
310-360mg/day
On a plate:
- 28g sunflower seeds
- 1 cup cooked edamame
- 1 cup cooked brown rice
- 28g brazil nuts
- 28g dark chocolate
- 1/2 avocado
As you can see, attention needs to be paid.
If you regularly eat nuts, seeds, legumes, whole grains, veggies and fruit and these foods form a big part of your diet, then it’s likely you’re meeting your daily needs. If not, book a 1:1 session and I will teach you how to learn to love and include these foods.
Magnesium & other functions
Magnesium performs many other important roles in the body like regulating nerve function, blood pressure, protein, bone, and DNA synthesis and so forth. It’s a really important nutrient to pay attention to.
Evidence also suggests magnesium adequacy can reduce premenstrual syndrome (PMS)symptoms.
A double-blinded placebo-controlled clinical trial of 150 women with PMS compared supplementation of magnesium only, supplemented magnesium + vitamin B12 and a placebo control group for 4 months and found a significant improvement in symptoms amongst the groups taking supplementation.
Again, maybe you don’t need to supplement, look at your diet first to see if you are eating enough magnesium rich foods.
I don’t default to supplementation first (food first approach here) as most of the doses given in these studies equate to the recommended daily intake for this nutrient which can be met through diet.
But sometimes, supplementation warranted, and I will recommend them in clinic.
Book a 1:1 if you are tired to confusing diets and want clarity to manage insulin resistance
