Magnesium is a big deal!
It’s the fourth most abundant mineral in your body.
Despite its necessity, almost half the U.S. population is falling short of the recommended minimum requirement for magnesium.
- What are the Roles of Magnesium in Your Body?
- Magnesium Rich Foods List
- Magnesium Rich Recipes
- What Are Some Symptoms of Magnesium Deficiency?
- Factors Increasing Your Demand for Magnesium
- Satiety Response
- Magnesium Upper Limit, Toxicity, and Side Effects
- Magnesium Stretch Target
- Magnesium Availability in the Food System and Obesity Correlation
- Synergistic Nutrients
- Absorption
- Storage
- Optimal Calcium:Magnesium Ratio
- Magnesium Bioavailability
- Why Does Keto Cause Magnesium Deficiency?
- Magnesium on a Ketogenic Diet
- Magnesium Supplements
- Does Magnesium Help with Keto Constipation?
- How Much Magnesium Should I Take on Keto?
- Nutrient Profile of the Highest Magnesium Foods
What are the Roles of Magnesium in Your Body?
Magnesium:
- is involved in more than 300 essential metabolic reactions,
- is necessary for muscle activity and nerve impulses,
- metabolises glucose and helps to normalise blood sugar,
- aides in protein synthesis,
- is required to detoxify hormones like estrogen,
- modulates the release of stress hormones, and regulates them,
- helps produce DNA, RNA, and the master antioxidant glutathione,
- plays a role in transporting calcium and potassium into, and out of, the cell,
- allows muscles to relax,
- transports ions like calcium and potassium,
- is required to produce ATP,
- is active in cell signalling,
- breaks down old neurotransmitters like histamine,
- helps synthesise collagen,
- regulates body temperature and blood pressure,
- normalises bowel movements,
- plays a crucial role in the structure of cell membranes and chromosomes,
- is necessary for detoxification and helps to detoxify substances like oxalate and salicylate, and
- aids in creating strong bones and teeth.
Getting adequate magnesium is helpful for:
- exercise performance,
- stress management,
- fighting depression,
- regulating anxiety,
- hormonal imbalances,
- muscle soreness and chronic pain,
- fluid balance,
- constipation,
- managing insulin resistance and Type-2 Diabetes,
- lowering blood pressure,
- reducing inflammation,
- helping you to get a better night sleep,
- Energy production,
- heart health,
- immunity,
- detoxification,
- preventing migraines, and
- improving PMS symptoms.
A lack of magnesium is strongly associated with cardiovascular disease. Studies have shown that people who die of heart attacks often have low magnesium levels.
While we should be getting a lot of magnesium on a daily basis, this has become difficult for a few reasons:
- Our soils have become depleted and void of magnesium from soil degradation and over-farming. Soil exploitation has not only contributed to magnesium deficiency but to shortfalls of other minerals and vitamins found in food as well.
- Because magnesium is rapidly used up to metabolise glucose, and in times of stress, the mingling of the modern food environment, and the go-go-go of the western world has further exacerbated deficiency.
Magnesium Rich Foods List
Magnesium dense foods can be found in plant or animal foods. However, magnesium is a vital component of chlorophyll which gives plants their green colour. It is therefore present in vegetables, particularly green ones. Some popular sources of magnesium are listed below.
Plants
- dark chocolate
- parsley
- zucchini
- kale
- cucumber
- lettuce
- flax seeds
- asparagus
- broccoli
- sauerkraut
- cabbage
- kale
- chard
- spinach
- brown rice
- lima beans
- avocado
- chickpeas
- banana
Animal
- milk
- hard goat cheese
- non-fat yogurt
- egg white
- liver
- parmesan
- beef
Seafood
- shrimp
- salmon
- mackerel
- snails
- scallops
- caviar
- halibut
Nuts & Seeds
- brazil nuts
- cashews
- sunflower seeds
- almonds
- peanuts
- hazelnuts
See top foods high in magnesium on Nutrient Optimiser for more detail.
Magnesium Rich Recipes
NutriBooster recipes that provide the most magnesium include:
- tuna & crab poke bowl (pictured)
- Sue’s salad
- avocado, banana & cacao smoothie
- cauliflower & spinach soup
- pesto zoodles
What Are Some Symptoms of Magnesium Deficiency?
Because magnesium plays a role in so many vital functions, lower intakes of magnesium are associated with a wide range of conditions, including:
- insulin resistance and hyperglycemia,
- Type-2 Diabetes,
- oxidative stress,
- hormonal imbalance,
- depression or anxiety,
- a pro-inflammatory state,
- atherosclerosis,
- anemia,
- anxiety,
- cold hands and feet,
- chronic fatigue,
- adrenal imbalances,
- concentration issues, ADD, or ADHD,
- seizures,
- depression,
- hypothermia,
- hypertension,
- insomnia,
- kidney stones,
- water retention,
- muscle cramps,
- premenstrual syndrome (PMS),
- irregular heartbeat, and
- neurotic behaviour.
Factors Increasing Your Demand for Magnesium
You may need more magnesium if you:
- are very active,
- drink a lot of alcohol,
- suffer from chronic fatigue,
- have metabolic acidosis,
- suffer from metabolic syndrome,
- have fibromyalgia,
- have any type of muscle pain or soreness,
- eat a high fat ketogenic diet,
- have epilepsy,
- are chronically stressed,
- have an inflammatory condition,
- are depressed or anxious,
- consume excessive phytates from cereals,
- have heart disease,
- are breastfeeding, or
- have high blood pressure.
Satiety Response
Our satiety analysis shows that foods with more magnesium tend to impact satiety substantially. Optimisers who consume more dietary magnesium per calorie tend to eat up to 22% fewer calories per day!

The average magnesium intake for Optimisers is 460 mg per 2000 calories with an 85th percentile intake of 690 g per 2000 calories from food. This is significantly greater than the Estimated Adequate Intake of 350 g per day and the RDI of 420 g per day for men, which are based on studies that looked at deficiency.
Magnesium Upper Limit, Toxicity, and Side Effects
An Upper Limit for magnesium of 0.35 g per day from supplements is set based on gut tolerance. While higher magnesium levels from food are not a problem, you could find yourself spending some extra time on the toilet if you overdo your magnesium supplementation.
Because excessive amounts of magnesium prompt a run to the bathroom, magnesium is an active ingredient in many laxative supplements. Magnesium draws water into the large intestine, forcing a bowel movement (when taken in high amounts).
Magnesium Stretch Target
Given the strong satiety response to magnesium and the numerous health benefits, we recommend a stretch target of 0.825 grams per day for men and 0.66 grams per day for women of magnesium from food. Once you start to get the hang of nutrient density, you could ‘level up’ by working to achieve these stretch targets to optimise your nutrition.
nutrient | men | women |
magnesium (g) | 0.825 | 0.66 |
Magnesium Availability in the Food System and Obesity Correlation
The amount of magnesium in the food system has declined since the widespread implementation of chemical fertilisers in the 1940s. Their introduction has since enabled crops to be grown in the same field without resting or replenishing them with nutrients like magnesium (data from USDA Economic Research Service).
Interestingly, the decrease in magnesium in the food system correlates with increasing obesity.
Nutrient | correlation with obesity |
sodium (g/2000 cals) | -96% |
calcium (g/2000 cals) | -96% |
cholesterol (g) | -96% |
saturated fat (%) | -92% |
potassium (g/2000 cals) | -91% |
vitamin A (RAE/2000 cal) | -81% |
phosphorus (g/2000 cal) | -80% |
vitamin B12 (mg/2000 cal) | -70% |
magnesium (mg/2000 cal) | -33% |
Magnesium-rich products are often unprocessed foods. Thus, someone whose diet revolves around processed foods would struggle to get enough magnesium.
Synergistic Nutrients
Magnesium works synergistically with vitamins B1, B6, C, D, potassium, boron, calcium, and glucose. This means it needs adequate amounts of each of these minerals (not just one) to work properly.
Thus, magnesium supplementation of just magnesium often isn’t very effective. Instead, consuming magnesium-rich foods usually contains the remaining spectrum of nutrients for this mineral to do its job.
Absorption
Magnesium is absorbed in your duodenum and ileum. Typical absorption rates are 30 to 40%. Excess magnesium is excreted in the urine (and feces, if in excess). Magnesium is known to have an acute laxative effect, meaning supplemental magnesium is often not absorbed well.
Storage
Magnesium is stored in your bone, teeth, muscles, liver, pancreas, and non-muscular soft tissue. The body regularly releases this mineral into the bloodstream to buffer and maintain a constant pH.
Optimal Calcium:Magnesium Ratio
Calcium and magnesium are closely interrelated. Your body needs adequate magnesium to use calcium properly, and vice versa. Magnesium deficiency, therefore, affects calcium metabolism and alters certain hormones that regulate calcium.
At the same time, calcium and magnesium compete with one another and interfere with the other’s functions if they are out of balance.
High intakes of calcium interfere with magnesium status by reducing intestinal absorption and increasing urinary losses. Additionally, magnesium deficiency is known to induce calcium deficiency. Magnesium may prevent calcium from contracting muscles when the ratio of magnesium to calcium is imbalanced and when magnesium levels are far too high.
Our satiety analysis shows that people who get more calcium than magnesium tend to eat less. So if weight loss is your goal, you should focus initially on getting adequate dietary calcium.
The average calcium: magnesium ratio of Optimisers is 2.9.
Nutrient Optimiser helps you manage your calcium: magnesium ratio to ensure that you’re not emphasising nutrients that exacerbate existing imbalances.
Magnesium Bioavailability
Minerals like magnesium are more likely to be plentiful in fresh and raw meat. But unfortunately, minerals are lost from the blood and juices of animal foods through processing and cooking.
However, magnesium absorption does not appear to be affected by consuming a plant-based versus animal-based diet. Magnesium is a nutrient absorbed similarly from plant and animal foods whether you consume a carnivorous diet or a plant-based diet.
Why Does Keto Cause Magnesium Deficiency?
Magnesium is one of the minerals whose deficiency contributes to “keto flu” when people switch to a low carb or ketogenic diet.
The kidneys regulate magnesium levels, and your body upregulates insulin to help the kidneys hold onto essential minerals like magnesium that can be harder to find on a reduced carbohydrate diet.
Dietary carbohydrates are stored as glycogen in muscles. Around three grams of water is stored in the muscles for every gram of glycogen. When dietary carbs are decreased, all of this water is released along with the minerals stored in the tissues.
Magnesium on a Ketogenic Diet
Several essential minerals tend to be harder to get on a keto diet because it limits high-carbohydrate plant-based foods. Hence many people on a keto diet feel better when they supplement magnesium.
In addition, foods highest in magnesium, like non-starchy green vegetables, tend to be lower in fat and higher in fibre. Therefore, if you prefer a lower carb or ketogenic diet, you should make an extra effort to prioritise non-starchy green vegetables to ensure you are getting adequate magnesium.
Magnesium Supplements
Magnesium is a nutrient worth supplementing if you consistently fall short of your recommended daily intake from your diet. However, this can be challenging because you will need to consume a quantity of powder or pills to boost your magnesium intake if your diet is low.
For example, you would need to consume 3 g of magnesium citrate powder to get the Daily Recommended Intake of 420 mg of magnesium. However, you would need to supplement with 8.5 g of powder to meet the men’s 1.25 g stretch target.
This can be problematic because this is a large volume of powder to consume. Secondly, it may give you diarrhea if your body is not used to absorbing magnesium in this form or this quantity, particularly if you have digestive issues. Hence, you should strive to get as much magnesium as possible from food and only use supplements to top up, if necessary. As always, start slowly.
Does Magnesium Help with Keto Constipation?
A ketogenic diet is known to have diuretic effects, resulting in someone following the diet peeing out many of their electrolytes, such as magnesium, potassium, sodium and calcium.
Because magnesium is harder to find on a ketogenic diet that does not emphasise non-starchy vegetables and is excreted more rapidly, we can see symptoms of low levels like constipation.
As a result, supplying the body with adequate magnesium can help to regulate bowel movements.
How Much Magnesium Should I Take on Keto?
Someone following a ketogenic diet should aim for the same stretch targets of all of their nutrients as someone who is not. This is to avoid deficiency due to consuming too little and prevent imbalances from consuming too much.
To determine how much magnesium you should be consuming as a supplement on a ketogenic diet, get an idea of how many milligrams you naturally consume on your low-carb diet by tracking your foods for a few days on Cronometer.
Once you get a baseline of what you’re getting already, look to supplement the milligrams you’re falling short of. This method will prevent you from getting too much or too little magnesium if you’re unaware of how much you get from food.
Green and leafy vegetables like chard and spinach, nuts, dark chocolate, and other green vegetables are keto-compliant foods high in magnesium.
If you are eager to supplement with magnesium, check out our Optimised Electrolyte Mix recipe that contains potassium, magnesium and sodium in optimal ratios. These are all excellent ways to incorporate supplemental magnesium without overdoing any of these minerals.
Nutrient Profile of the Highest Magnesium Foods
The nutrient fingerprint shows that magnesium is reasonably easy to get from a nutrient-dense diet. Foods that contain more magnesium tend to be higher in fibre and lower in fat.
How Do I Calculate my Magnesium Intake?
If you’re interested in checking if you’re getting enough magnesium in your diet, you can check your nutrient profile using our Free 7-Day Nutrient Clarity Challenge.
After a week of tracking your current diet in Cronometer, Nutrient Optimiser will give you a prioritised list of foods and NutriBooster recipes that will help you plug your current nutritional gaps.
Level Up Your Nutrient Density
To help you level up your nutrient density, we’ve prepared a Nutritional Optimisation Starter Pack to ensure you are getting plenty of all the essential nutrients from the food you eat every day.
The free starter pack includes:
- Maximum Nutrient Density Food List
- Sample Maximum Nutrient Density Recipe Book
- Sample Maximum Nutrient Density Meal Plan.
To get started today, all you have to do is join our new Optimising Nutrition Group here.
Once you join, you will find the Nutritional Optimisation starter pack in the discovery section here.
Nutrient Density Index
Minerals
Vitamins
- Vitamin A
- Vitamin E
- Thiamine (B1)
- Riboflavin (B2)
- Niacin (B3)
- Pantothenic acid (B5)
- Vitamin B6
- Folate (B9)
- Vitamin B12
- Vitamin C
- Vitamin D
- Choline
- Vitamin K1