You don’t have to be on a Keto Diet to have an appreciation for magnesium and the essential role it plays in our health. This nutritional powerhouse is one of the most abundant minerals in the body, involved in a number of reactions including protein synthesis, energy production, blood sugar control, and blood pressure regulation. Magnesium also helps to regulate nerve function (calming the mind, promoting relaxation and improving sleep), enables optimal digestion, and promotes healthy muscle function and a normal heart rhythm. Bottom line: Magnesium is vital for your body to function properly.
Causes of Low Magnesium
In spite of its strategic role in numerous body functions, magnesium is often lacking in the average American diet, which is highly processed. Your risk of an actual magnesium deficiency also increases if you are taking a diuretic medication for blood pressure or if you habitually over-consume alcohol. In addition, elevated blood glucose levels, associated with diabetes, increase the loss of magnesium in the urine, which in turn lowers blood levels of magnesium. Research has linked low levels of magnesium to insulin resistance, which often precedes the development of type 2 diabetes.
Why Magnesium is Important on a Keto Diet
If you’re new to ‘Keto’, an inadequate magnesium intake can contribute to symptoms commonly known as the ‘Keto Flu’. Magnesium is one of the minerals that can be rapidly depleted during the first few weeks on a ketogenic diet because of the increased water loss through increased urination. Along with the water that is being dumped through your kidneys, your body is also losing magnesium and other electrolytes. If you’re not eating enough magnesium to compensate for any losses, you can experience symptoms such as muscle cramps or spasms, and fatigue. A chronically low intake of magnesium can progress to a rare, but more serious deficiency exhibited by symptoms such as seizures, heart spasms and an abnormal heartbeat.
Dietary recommendations: The current Recommended Daily Allowance (RDA) for magnesium is 400-420 mg/day for men and 310-320 mg/day for women1.
30 ‘Keto-Friendly’ Food Sources of Magnesium2:
Food Amount of Food mg of Magnesium
Hemp seeds 1 oz 170 mg
Spinach, cooked 1 cup 157 mg
Brazil nuts 1 oz 107 mg
Broccoli, steamed 1 cup 102 mg
Sesame seeds, roasted 1 oz 101 mg
Almond butter 2 Tbsp 90 mg
Flaxseed Meal 3 Tbsp 82 mg
Almonds, roasted 1 oz 76 mg
Sunflower seeds, roasted 1 oz 76 mg
Pumpkin seeds, roasted 1 oz 75 mg
Cashews, dry roasted 1 oz 74 mg
Edamame, frozen, prepared 1 cup 50 mg
Peanuts, roasted 1 oz 50 mg
Peanut butter, smooth 2 Tbsp 49 mg
Hazelnuts 1 oz 46 mg
Walnuts 1 oz 45 mg
Avocado, cubed 1 cup 44 mg
Tuna, canned, drained 1 cup 42 mg
Pecans 1 oz 39 mg
Shrimp, cooked 3 oz 39 mg
Tofu ½ cup 37 mg
Pistachios, roasted 1 oz 31 mg
Scallops, steamed 3 oz 31 mg
Mussels, cooked 3 oz 31 mg
Veal, lean, cooked 3 oz 27 mg
Cocoa Powder 1 Tbsp 26 mg
Sirloin steak, cooked 3 oz 26 mg
Salmon, Atlantic, cooked 3 oz 26 mg
Spinach, raw 1 cup 24 mg
Chicken breast, roasted 3 oz 22 mg
When to Supplement
If you are ever in doubt whether to supplement with magnesium, the decision should be made with the input from your health care team. Magnesium can interfere with a number of prescription drugs, including certain blood pressure medications, statins, and antibiotics. Daily supplementation may indeed be necessary if you’re already experiencing symptoms of magnesium depletion. Magnesium supplements come in a variety of forms with varying rates of absorption. Taking a glycinate or malate form of this mineral might be better tolerated if you have a sensitive stomach, and taking any magnesium supplement with meals can also help to minimize gut distress.
Take Home Message
Whatever your motivation for choosing to go ‘Keto’ —whether to manage a chronic disease such as diabetes, for weight loss, or for increased physical and mental energy (or all of the above!)—ensuring an adequate magnesium intake should be one of your top priorities. In spite of the wide range of magnesium-rich foods that are compatible with the Keto Diet, it might still be a struggle for some to try to hit the RDA for this vital mineral. If this describes you, or if you are currently experiencing severe symptoms of the ‘Keto Flu’ (due to a lack or loss of magnesium in the body), supplementation with magnesium may provide an added benefit.
- NIH Office of Dietary Supplements:https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/#h2
- USDA Food Composition Databases: https://ndb.nal.usda.gov/ndb/search/list?home=true