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Magnificent Magnesium

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Magnesium is in high demand by the body as it is involved in more than 325 different metabolic reactions! It helps the body to metabolize fat, protein and carbohydrate enabling it to get ‘energy’ from the food we eat. People who eat more foods that contain magnesium tend to be less at risk of diabetes. This magnificent mineral also aids in the proper functioning of your genes, DNA synthesis and for cell replication (your body’s cells are constantly being renewed). Magnesium helps to both relax and contract your muscles which is very important for those who exercise and especially so for athletes. Magnesium is good for your heart and blood vessels and its very important in bone health by helping calcium and phosphorus work to make a strong skeleton. People who get a lot of magnesium in their diet also tend to have lower blood pressure.

Despite magnesium’s vital role, most people aren’t getting enough from the foods that they eat. Based on analysis of dietary intakes, it’s estimated that we’re getting less than half the amount we did 100 years ago, down from about 500mg/day to 175-225mg/day. Worse, magnesium intake is still falling. We can blame this on modern day foods that are highly processed and refined. To make matters worse, researchers suggest that the amount of magnesium required for optimum health has been underestimated in the past. While there isn’t an easy test to determine magnesium status (i.e. a blood test), there are some nutritional risk factors and eating habits that are associated with low magnesium intake:

  • If you eat more white flour products instead of 100% whole wheat
  • If you don’t eat a lot of green leafy vegetables
  • If you don’t eat many nuts, seeds, and legumes
  • If you regularly eat or drink sugar or sugary products/beverages
  • If you drink alcohol regularly
  • If you follow a calorie-restricted or high-protein, low carbohydrate diet

How much magnesium do you need?

Age Women Men
14-18 360mg 410mg
19-30 310mg 400mg
31+ 320mg 420mg

Magnesium is abundant in unrefined whole grain products, such as 100% whole wheat bread and cereals, green leafy vegetables (spinach and kale), nuts and seeds and legumes (lentils, kidney beans, chick peas etc). The following are good food sources.

Food Magnesium content (per 100g or 3oz)
Pumpkin seeds 532mg
(177mg/ 1/3 cup)
Almonds 300mg
(100mg/23 almonds)
Brazil nuts 225mg
(75mg/8 nuts)
Peanuts (roasted) 183mg
(124mg/ ½ cup)
Walnuts 158mg
(53mg/7 walnuts)
Rice (whole grain brown) 110mg
(55mg/ ½ cup cooked)
100% Whole grain bread 85mg (about 3 slices)
Spinach 80mg
(about ½ cup cooked)
Cooked legumes 40mg
(about ½ cup)
Broccoli 30mg
(about 1 cup chopped)
Banana 29mg
(1 medium)

What’s the bottom line? Given the potential for sub-optimal magnesium intake, anyone not already doing so should make a conscious effort to eat more magnesium-rich foods every day. Even simple changes like eating more 100% whole grain products and boosting your intake of nuts and seeds can make a big impact. In addition to eating more magnesium rich foods, reach for a multivitamin/mineral – look for one with at least 100mg of magnesium. A word of caution: taking more than 400mg of magnesium from supplements can cause diarrhea.

Essentiality

Magnesium is an essential element in human metabolism and is required for over 300 enzyme reactions and inadequate levels of magnesium can severely affect cardiovascular, neuromuscular, and renal functions.

Under normal conditions, magnesium levels are carefully regulated, and short-term dietary deficiencies can be overcome by the large available pool of magnesium in bone. However, depletion can occur as a result of vomiting, diarrhea, use of certain diuretics, alcoholism, and protein malnutrition. Deficiency produces weakness, mental disorder, lessening of muscle control, and gastrointestinal disorders. It has been suggested that long-term magnesium deficiency may be a factor in cardiovascular disease.

Glossary

Blood Pressure
Description:
is a measurement of the force applied to the walls of the arteries as the heart pumps blood through the body. The pressure is determined by the force and amount of blood pumped, and the size and flexibility of the arteries. Blood pressure readings are usually given as two numbers: for example, 110 over 70 (written as 110/70). The first number is the systolic blood pressure reading, and it represents the maximum pressure exerted when the heart contracts. The second number is the diastolic blood pressure reading, and it represents the pressure in the arteries when the heart is at rest.
Calcium
Description:
This is the most important mineral for building bone density, preventing bone loss and treating osteoporosis. Calcium also regulates your heartbeat, helps with blood clotting and makes your muscles contract. Milk products, fortified soy beverages, dark leafy green vegetables, and almonds are all sources of calcium.
Carbohydrate
Description:
One of the three macronutrients, along with protein and fat, that supplies energy (calories) to the body. There are three categories of carbohydrates: sugars, starch and fiber.
Diarrhea
Description:
is commonly described as passage of = 3 loose or watery stools/day.  The more numerous the watery stools, the more dangerous the diarrhea
Fat
Description:
Is one of the nutrients, along with protein and carbohydrate, that supplies energy (calories) to the body. Dietary fats include saturated (animal flesh, butter, margarine, processed and fried foods), trans (hydrogenated oils) and unsaturated (vegetable oils). Unsaturated fats are the preferred type for health reasons.
Legumes
Description:
Legumes are seeds that grow in pods. Legumes are high in fibre, low in fat and a good source of protein. Beans, lentils, peas, soybeans, and peanuts are all examples of some common legumes.
Sugars
Description:
A group of carbohydrates that help make our food sweet. Glucose, fructose, sucrose and lactose are some examples. The different names indicate that each sugar has a different chemical structure.

Provided by the Ministry of Health Promotion.

Ontario

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