Have you ever had a craving to eat dirt? It sounds bizarre, but people have been eating dirt for a long time. Why? Pliny the Elder, an ancient Roman author and natural philosopher documents people eating the soil on the Greek island of Lemnos. Hippocrates, the father of western medicine, documents the practice as early as 400 BC. Archeologists at the prehistoric site of Kalambo Falls discovered evidence of our ancestors Homo habillis eating a calcium-rich white clay 200,000 years ago.
Even today you can find small bags of “white dirt” for sale at local groceries and convenience stores in the southeastern United States. Dirt isn’t the only strange thing people eat. People who suffer from an iron deficiency may experience an uncontrollable urge to eat or chew on crushed ice. Other people may crave chalk.
What’s behind these strange obsessions? Scientists don’t know for sure, but one theory is that the body is craving critical minerals that are missing from the diet. A recent study showed people who engaged in pica (the scientific name for eating dirt or other non-food items) were 2.35 times more likely than average to have a deficiency in iron or zinc. The proper intake of minerals is essential for your body to function. As an athlete, you may be at an increased risk for some mineral deficiencies, but what if you eat a healthy ‘balanced diet?’ If you are paying attention, following a healthy diet, and eating all your veggies you might believe that you’re getting all your required minerals, but you’d be wrong.
The American Dietetic Association is responsible for establishing the Reference Daily Intakes (RDI). The RDI replaces the older RDA and provides a list of the required minimal daily intake of vitamins, minerals, and nutrients needed to prevent nutritional deficiencies. A recent study published in the Journal of the International Society of Sports Nutrition analyzed over 70 different diets followed by athletes and sedentary subjects (who were actively looking to improve their nutritional intake). The study found that all of them fell short of supplying 100% of the RDI of micronutrients and minerals. Not a single diet analyzed by the researchers supplied all of the required micronutrients!
The results of this study become even more critical when you understand that the RDI is not designed for athletes who are seeking optimal performance from their bodies. Instead, they serve as a bare minimum for everyone in the US who is more than four years old. Athletes, who typically need more nutrients than the average person, are getting less of some nutrients than recommended for a typical 5-year-old. So, if you’re not supplementing with minerals and relying on your diet alone to supply these critical nutrients, you’re almost certainly deficient in some of them.
Essentials for the Jiu-JItsu Athlete
As a jiu-jitsu athlete your diet is most likely to be too low in calcium, iron, zinc, and magnesium.
Calcium acts like cement in the construction of your bones. It is the most abundant mineral in the body, present in every cell. You have about 3lbs of calcium in your body, of which 98% is in your bones, 1% in your teeth, and the rest in other tissues and the blood.
Calcium does more than just build strong bones, though; it helps regulate heart and muscle contraction, as well as nerve conduction. So, while most of your calcium is sequestered in the bones, it’s this blood calcium level that is most critical. If your diet doesn’t supply enough calcium, your body will draw it out of the bones to try and maintain adequate blood levels.
Adult athletes should try to consume at least 1500mg of calcium daily. Some of the best food sources of calcium are:
Milk – 240mg/cup
Hard cheese – 240mg/30g serving
Sardines – 240mg/60g serving
White Beans – 132mg/200g serving
Dried Figs – 96mg/60g serving
Broccoli – 112mg/120g raw serving
When supplementing with calcium, some forms are much easier for your body to utilize than others (they are more bio-available). The most common form of calcium is calcium carbonate, which is very inexpensive, but also very difficult for your body to absorb. A better choice would be calcium citrate or calcium orotate.
Make sure to take your calcium supplements with food and with Vitamin D, which is critical in helping absorption. If you needed one more reason to avoid cola, one serving of soda can leach over 100mg of calcium out of your body due to the high phosphorus content.
It’s also critical to make sure you are getting enough magnesium in your diet, especially when supplementing with calcium. Getting too much calcium without enough magnesium can lead to hardening of the arteries – otherwise known as calcification.