How the Government Determined the RDA for copper at 0.9 Milligrams

Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc

While they have indicators to diagnose copper deficiency, there is no report that they used them to see if their recommendation of 0.9 mg causes copper deficiency!

What they did was use incomplete calculations to determine copper excretions in copper deprived people, (they never tested a normal population!) which came to .5 mg of copper. They then tested .58 mg of copper, and 8/10 tested deficient. Then, they just arbitrarily increased it to .9 mg, with no further testing to see if that was sufficient. That is madness. And certainly not scientific.

For reference sake, babies get .25 mg in breast milk, in typical mothers who, themselves may be copper deficient. Lack of copper causes depression. Anyone heard of postpartum depression? For a grown man who weighs 20 times more than an infant, that implies 5 mg. The highest copper foods, a pound of liver contains 64 mg of copper. A pound of oysters contains 37 mg. And a historical RDA for copper was 3 mg. (I have to find a source for that.)

p. 229: “Several indicators are used to diagnose copper deficiency. These indicators—serum or plasma copper concentration, ceruloplasmin concentration, and erythrocyte superoxide dismutase activity—are low with copper deficiency and respond to copper supplementation”

p. 230: “Serum copper concentration is a reliable indicator of copper deficiency, falling to very low concentrations in copper-deficient individuals.”

“Ceruloplasmin concentration is also a reliable indicator of copper deficiency. Ceruloplasmin carries between 60 and 95 percent of serum copper, and changes in serum copper concentration usually parallel the ceruloplasmin concentration in the blood. Ceruloplasmin, too, falls to low concentrations with copper deficiency, far below the lower end of the normal range of 180 mg/L, and it responds quickly to repletion (Danks, 1988).”

p. 233 Copper Balance // Balance studies have been used in the past to estimate dietary recommendations. Numerous copper balance studies in humans have been conducted over a wide range of intakes (Mason, 1979). Unfortunately, there are a number of problems with this approach, as reviewed by Mertz (1987). Copper balance, which can be achieved over a broad range of dietary copper intakes, reflects prior dietary intake; thus long adaptation is required for results to be meaningful. Seldom are studies long enough. Such studies are prone to numerous errors, and data from some studies would suggest that an unacceptable amount of copper would accumulate over time if these levels of retention were continued. In addition, miscellaneous losses, while small, are very difficult to quantify. Therefore, balance studies were not used as an indicator of copper status.

p. 234 Zinc: “This zinc-induced inhibition of copper absorption could be the result of competition for a common, apically oriented transporter or the induction of metallothionein in intestinal cells by zinc. Because this protein has a higher binding affinity for copper than for zinc, copper is retained within enterocytes and its absorption is reduced.”

“High iron intakes may interfere with copper absorption in infants.”

p. 237-8: Human milk contains 250 mcg/L of copper. Cows milk contains 60-90 mcg/L. “Copper deficiency has been observed in infants fed cow milk (Cordano et al., 1964; Levy et al., 1985). ”

p. 240: “Platelet copper concentration, however, declined significantly for eight of ten women fed 570 µg/day and increased with supplementation.”

“While an EAR based on the first two studies was estimated at 550 µg/day, the latter study suggests that 600 µg/day may be a marginal intake in over half of the population. Therefore, another increment was added to cover half of the population, and the EAR was set at 700 µg/day.
” This seems crazy to me. They know 580 is too low, so they arbitrarily move the number to 700??! Where is the science? Where is the testing? Why did they not say what the supplementation level was to fix the deficiencies at 0.57 mg/day

p. 241: They do something very weird. On either copper restricted diets, or zero copper diets, they try to estimate copper losses. They they imagine this might be a lower minimum. But this fails to take into account that the body might (and actually does) hold on to copper more tightly under such conditions. IE, more copper is absorbed, at a higher percentage, when copper deficient. So, they are measuring copper excretion in copper deficient people.

“There are no data on obligatory copper losses in healthy people” This is troubling. It’s as if they have avoided looking at normalcy, on purpose.

p. 242: “Other losses, such as hair, nails, semen, or menstrual, have not been measured, and it is assumed they are similar to surface losses. Therefore the amount of absorbed copper needed to replace obligatory losses is 344 µg/day (240 + 20 + 42 + 42). Copper absorption at this level of intake is approximately 75 percent. Therefore, 460 µg/day of dietary copper would be the minimum amount required to replace obligatory losses. Endogenous fecal copper was 50 µg/day higher at 380 µg/day than at 460 µg/day, and so 50 µg/day was added to endogenous fecal losses to account for the increase that occurs between 380 and 460 µg/day. Thus 510 µg/day (460 + 50) of dietary copper is required to replace copper losses from all sources and to achieve zero balance.”

My comment: they are specifically trying to come up with a minimum daily intake (EAR Estimated Average Requirement) that will be too low and create deficiencies; and they already know a higher level 580 ug/day or 0.58 mg creates deficiencies in 8/10 women! Problems. Copper comes out in the hair at high concentrations, and hair is not measured. Copper goes into the skin as copper is used to create a tan. Copper is therefore used up more when tanning. They are not measuring copper being used up through exercise, or copper being blocked by other supplements. This is HORRIFIC science. Well, it is government science.

p 242,243: “The data available to set an EAR are limited for men and women, as well as the number of levels of dietary copper in depletion/repletion studies. Thus, a CV of 15 percent is used. The RDA is defined as equal to the EAR plus twice the CV to cover the needs of 97 to 98
percent of individuals in the group (therefore, for copper the RDA is 130 percent of the EAR). The calculated RDA is rounded to the nearest 100 µg.
RDA for Men 19–50 years 900 µg/day of copper 51–70 years 900 µg/day of copper > 70 years 900 µg/day of copper
RDA for Women 19–50 years 900 µg/day of copper 51–70 years 900 µg/day of copper > 70 years 900 µg/day of copper”