Sodium and Potassium
Cells use what is called a sodium-potassium pump to create gradients of ions in order for nerves to function. Basically, these nutrients are needed for you body to create the electricity that drives the nervous system. This aids in muscular contractions as well, especially those of the heart. A deficiency in either of these electrolytes reduces the ability for muscles to function, and can result in weakness, twitching and cramps. Athletes especially have an increased need for these minerals as they use them through muscular contractions, and lose them through sweat. This is particularly important for those on a ketogenic diet, as restricting carbs reduces water retention, resulting in lower concentration of electrolytes. I recommend using sea salt to either salt your food liberally, or add a pinch to your water in the morning. Sodium is hydrophilic, which means water-loving and subsequently it can help you retain water if you're often thirsty. For those worried about sodium and kidney damage or blood pressure, know that most studies on salt are done with regular table salt that often has additives. Namely, sodium silico-aluminate and sodium acetate, which have been shown to cause kidney problems, mineral malabsorbtion, water retention and elevated blood pressure. Historically, the amount of salt consumed on a daily basis was pretty high. Methods of preservation before refrigeration were most commonly salting meat or lacto-fermenting vegetables, which also requires salt.
Good sources of potassium include beet greens, beans, spinach, yogurt, sweet potato, banana and avocado.
Magnesium and calcium
Magnesium and calcium are two more electrolytes that help with muscular contractions. This time interacting with actin and myosin proteins, calcium contracts the muscle fibers while magnesium relaxes them. Good sources of magnesium are coconut water, swiss chard, almonds, avocados, pumpkin seeds and dark chocolate.
Collagen
Prior to supermarkets, we didn't have the ability to only buy choice cuts of meat like chicken breasts. We ate the entire animal, head to tail. The collagen content in the tougher, sinewy parts of animals is much higher than in the lean meat.
Collagen seems to be the latest food fad, with many stores now carrying ready to drink bone broth. Problem is, you'll pay out the nose for the convenience. That's fine if you have the money, but a cheaper way is to simply buy a rotisserie chicken and make your own. As soon as you get it home, pick the meat off and store it in containers for later. Put the leftover bones in a large pot with a lid, cover with water and add salt. A dash of vinegar supposedly helps extract minerals, though it isn't imperative. Other good sources of collagen are skin, and any part of an animal with a lot of connective tissue. These are the tough cuts of meat, that can be made delicious and tender with long, slow cooking.
Iodine and Selenium
Iodine is used by your thyroid to manufacture Thyroid Stimulating Hormone,or TSH. Your thyroid drives the speed of your metabolism and many other bodily functions including regulating your body temperature. Without adequate Selenium, iodine levels may become high in the thyroid, leading to cell damage. Iodine is most commonly found in seafood and seaweed, while Brazil nuts offer impressive quantities of selenium.
Vitamin A
Mostly found in organ meats, this is another nutrient that most of us are deficient in. Plant sources of vitamin A exist as beta-carotene, but are not as bioavailable as retinol from animal sources. Vitamin A is important for growth, immune function and vision, specifically for low light and color vision. Excessive Vitamin A can cause problems during pregnancy. Liver or pastured eggs are a good source of vitamin A.
By bringing attention to these commonly overlooked nutrients, we can dial in our diets to help optimize how our bodies function.