98 Joel Fuhrman, M.D.To make matters even worse, you pay an extra penalty from a diet
so high in fat and protein to generate a chronic ketosis. Besides the
increased cancer risk, your kidneys are placed under greater stress and
will age more rapidly. It can take many, many years for such damage
to be detected by blood tests. By the time the blood reflects the ab-
normality, irreversible damage may have already occurred. Blood tests
that monitor kidney function typically do not begin to detect prob-
lems until more than 90 percent of the kidneys have been destroyed.
Protein is metabolized by the liver, and the nitrogenous wastes
generated are broken down and then excreted by the kidney. These
wastes must be eliminated for the body to maintain normal purity
and a stable state of equilibrium. Most doctors are taught in medical
school that a high-protein diet ages the kidney.^15 What has been ac-
cepted as the normal age-related loss in renal function may really be
a cumulative injury secondary to the heavy pressure imposed on the
kidney by our high-protein eating habits.^16
By the eighth decade of life, Americans lose about 30 percent of
their kidney function.^17 Many people develop kidney problems at
young ages under the high-protein stress. Low-protein diets are rou-
tinely used to treat patients with liver and kidney failure.^18 A recent
multitrial analysis showed that reducing protein intake for patients
with kidney disease decreased kidney-related death by about 40 per-cent.^19
Diabetics, who are at increased risk of kidney disease, are ex-
tremely sensitive to the stress a high-protein diet places on the kid-
ney.^20 In a large, multicentered study involving 1,521 patients, most
of the diabetics who ate too much animal protein had lost over half
of their kidney function, and almost all the damage was irreversible.^21
In my practice, I have seen numerous patients who have experi-
enced significant worsening of their kidney function after attempting
weight loss and diabetic control with high-protein diets. Coinci-
dence? I think not. Damage from such lopsided nutritional advice
can be very serious.Ketogenic diets, like Atkins's, have been used to treat children
with seizure disorders when medication alone is unresponsive. Med-
ical studies reveal that these diets can result in serious health conse-
quences. Investigators report a greater potential for adverse events
than had ever been anticipated. The dangers of these high-protein
diets include hemolytic anemia, abnormal liver function, renal tubu-
lar acidosis, and spontaneous bone fractures (despite calcium supple-
mentation).^22 Kidney stones are another risk of high-protein diets.^23