Trace Minerals

Selenium:

The USDA RDA for selenium is 55ug, but studies show that 200ug daily is the best for a healthy immune system (link and link), and preventing heart disease (link) due to it's co-factor role in glutathione peroxidase (do we really need reminding how important glutathione is?). This is easy to achieve 200ug if kidneys are included in a carnivore diet, the best plant source is brazil nuts (1-2 a day only, too much can cause toxicity).


Iodine:

Iodine is important for a healthy metabolism, as it's needed to make the thyroid hormones (and selenium is needed to turn inactive T4 into the active T3, another reason to get plenty of selenium). The USDA is 150ug, but this is the bare minimum determined needed to stop goitre (enlargening of the thyroid gland), the Japanese get 1-3mg a day (666-2,000% USDA RDA) (link) mostly from seaweed and so this amount seems perfectly safe. Also iodine deficiency seems to play a big role in breast cancer (link and link), the Japanese have very low breast cancer rates possibly due to their high iodine intakes. For these reasons I shall be recommending more iodine than the USDA, mostly from kelp/kombu flakes (these are the most iodine rich seaweeds: "Most Kelp or Kombu has about 2500 mcg/gm" (source)), shellfish are also another good source but just don't provide anywhere near as much iodine as kelp/kombu do. These will also provide many other trace minerals they we may not even realise are needed for health yet, so are a great addition to anyone's diet.

Cattle fed plenty of seaweed or in iodine rich soil (coastal) will have much more iodine in their flesh and organs, same for eggs of chickens fed seaweeds, but still no where near eating the seaweed itself.


Sulphur:

There are two main sources of sulphur from foods: thiols in plants, and the sulphur containing amino acids (cysteine and methionine) in animal foods. Thiols are good for their antioxidant properties but aren't good sources of usable sulphur for bodily structures, for that we need cysteine and methionine. Cysteine and methionine (via cysteine) are the best for boosting glutathione levels. I'm happy that a diet rich in eggs and meat will have plenty of sulphur.


Chromium:

The USDA was 50-200ug and has been lowered to 35ug for men and 25ug for women. Liver is a very rich source, and beef, eggs, chicken, oysters are also good sources. Chromium deficiency is rare and the only ones needing supplemental chromium are diabetics still eating lots of refined grains. I'm happy that a diet based on meat, eggs, with some liver will have more than enough chromium especially considering that less will be needed on a diet lacking dietary carbohydrates.


Biotin:

This vitamin is needed for gluconeogenesis so is important for a carnivorous diet, the best sources are egg yolks and liver, cheese also has some; raw egg whites without yolks can cause deficiency though. First signs of deficiency are hair loss and skin problems, though deficiency is rare unless consuming lots of raw egg whites or your food intake is just shakes or an IV without biotin.

From wiki: "Pregnant women tend to have a high risk of biotin deficiency. Nearly half of pregnant women have abnormal increases of 3-hydroxyisovaleric acid, which reflects reduced status of biotin.[25] Several studies have reported this possible biotin deficiency during the pregnancy may cause infants' congenital malformations, such as cleft palate." (link)

For this reason egg yolks and liver are even more vital for pregnant women. In China eggs are considered a fertility food and pregnant women will eat up to two dozen a day to ensure an intelligent child.

The RDA for adults is 30ug, and 35ug for pregnant women; though this amount for pregnant women is likely too little. 30ug can be found in 4oz/114g liver or ~1.5 eggs (source). For this reason I recommend plenty of eggs and liver in a carnivore diet, and lots during pregnancy/lactation.


Molybdenum:

This mineral is needed for xanthine oxidase to work, which if you've read my previous posts you'll recognise as that all important enzyme that makes uric acid to help us ward off scurvy on an ascorbic acid-free diet. It's also used for metabolising the sulphur-containing amino acids, cysteine and methionine, so is important in glutathione production.

Livers contain about 150ug per 100g, and very small amounts in eggs. The RDA is 45ug for adult, so a diet containing plenty of liver will have no issues. My new perfect carnivore diet contains ~70ug molybdenum.


Other Trace Minerals:

These include boron, nickel, strontium, vanadium, lithium, and silica. Because I can't find much data on food sources (the latter two should come from our water though) and nutrient interacts, I won't be including them in the cRDA project. Once more is known about these minerals and their need though I will expand the cRDA to include them.

Lithium and Silica:

These mineral should come from our water rather than food, but most water has them removed. When buying bottled water look for one listing silica on the label, most water has 5-25mg/L (source), Fiji brand is best for silica (920mg/L) though expensive, any that lists it on the label is likely a good source and also check with your water provider to the content in your tap water; other good sources of silica are edible clays. Low lithium in water levels is linked to suicides (source), very high levels are used to treat bipolar and schizophrenia, but tiny amounts prevent mental disorders such as criminal behaviours (source) in the general population, so much so that some scientists are calling for adding lithium to the water in areas where the content is low! Again ask your water provider, most bottle water is unlikely to list lithium.

A link on silicon.