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Reports from PCRM's Nutrition Department
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Report |

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Analysis of Health Problems Associated
with High-Protein, High-Fat, Carbohydrate-Restricted Diets
Reported via an Online Registry
Physicians Committee for Responsible Medicine
Updated May 25, 2004
Methods | Findings
| Discussion | Limitations|
Literature Cited | Appendix
Introduction
While a few recent studies have noted that high-protein,
carbohydrate-restricted diets facilitate modest short-term
weight loss,1-3 no studies to date have investigated
the long-term health consequences of consuming such diets
for weight-loss purposes.
Studies of general populations consuming diets high in fat,
particularly saturated fat (low-carbohydrate diets have not
been studied specifically) have shown increased risk of cancer,4-6
diabetes,7 and heart disease.7 Mixed
diets high in animal protein have been shown to increase the
risk of kidney problems,8,9 osteoporosis,10,11
and some types of cancer.12,13 These studies raise
concerns as to whether low-carbohydrate diets, which are typically
high in saturated fat and animal protein, might pose the same
risks. In addition, because fiber is found only in plant foods,
and high-protein, high-fat, carbohydrate-restricted diets
tend to be low in plant foods, these diets are also typically
low in fiber. In studies of general populations, low fiber
intake is associated with increased risk of colon cancer and
other malignancies,4 heart disease,7 diabetes,14,15
and constipation.16 Again, these studies raise
the question as to whether similar problems occur in low-carbohydrate
dieters.
Some high-protein, very-low-carbohydrate, weight-loss diets
are designed to induce ketosis. When carbohydrate intake or
utilization is insufficient to provide glucose to the cells
that rely on it as an energy source, ketone bodies are formed
from fatty acids. An increase in circulating ketones can disturb
the body’s acid-base balance, causing metabolic acidosis.
Evidence suggests that even mild acidosis can have potentially
deleterious consequences over the long run, including low
blood phosphate levels, resorption of calcium from bone, increased
risk of osteoporosis, and an increased propensity to form
kidney stones. 17
These findings raise concerns that high-protein, high-fat,
low-fiber, carbohydrate-restricted diets used for prolonged
periods may increase the risk of health problems, despite
the short-term weight loss that may accompany their use.
Herein, we summarize the reports of individuals who have
experienced health problems while on a high-protein, high-fat,
carbohydrate-restricted diet and have offered their information
through an online registry (www.AtkinsDietAlert.org/registry.html).
Methods
In the fall of 2002, the Physicians Committee for Responsible
Medicine (PCRM) began a pilot program to test the feasibility
of an online registry to identify people who may have suffered
health complications related to high-protein, low-carbohydrate
diets. A modest Internet advertising campaign was used to
notify consumers about the availability of this registry.
In November of 2003, PCRM held a news conference to highlight
the health problems suffered by some individuals using these
diets and to draw attention to the registry.
To report problems with high-protein, high-fat, carbohydrate-restricted
diets, individuals voluntarily visited www.AtkinsDietAlert.org
and filled out a form available on the site. The registry
specifically inquires about the following problems: heart
attack, other heart problems, high cholesterol, diabetes,
gout, gallbladder, colorectal cancer, other cancers, osteoporosis,
reduced kidney function, kidney stones, constipation, difficulty
concentrating, bad breath, and loss of energy. In addition,
many registrants indicated, in an “other problems”
box on the registry, that they had experienced certain other
problems while on low-carbohydrate diets. Many registrants
reported more than one health concern. Through the online
form, most registrants provided their contact information,
age, sex, previous health concerns, length of time on the
diet, reasons for choosing the diet, and other information.
The registration entries were self-reports and were not subject
to verification through medical record reviews or other methods,
nor was registration deemed to indicate a cause-and-effect
relationship. To help clarify the possible biological mechanisms
by which a high-protein, high-fat, carbohydrate-restricted
diet might lead to these problems, PCRM dietitians conducted
a nutrient analysis of the sample menus for the three stages
of the Atkins Diet as described in Dr. Atkins’ New
Diet Revolution (M. Evans & Co., 1999; pp. 257–259),
using Nutritionist V, Version 2.0, for Windows 98 (First DataBank
Inc., Hearst Corporation, San Bruno, Calif.).
Findings
As of December 15, 2003, 429 individuals reported experiencing
problems with high-protein, high-fat, carbohydrate-restricted
diets via the online registry. Table 1 lists the common health
concerns identified on the online form. Table 2 summarizes
health problems noted by seven or more individuals in the
write-in section of the form.
Table 1. Common Problems Reported by Registrants
44% reported constipation
40% reported loss of energy
40% reported bad breath
29% reported difficulty concentrating
19% reported kidney problems: kidney stones (10%), severe
kidney infections (1%), or reduced kidney function (8%)
33% reported heart-related problems, including 13 individuals
reporting heart attack, stent placement, or bypass surgery,
26 reporting arrthymias, 42 reporting other cardiac problems,
and 58 reporting elevated serum cholesterol levels
9% reported gallbladder problems or removal
5% reported gout
4% reported diabetes
4% reported colorectal (1%) or other cancers (3%)
3% reported osteoporosis
Table 2. Other Problems Reported by Seven or More
Individuals:
31 reported severe gastrointestinal problems including
irritable bowel syndrome, diverticulititis, ulcers, heart
burn, vomiting, severe abdominal pain, or cramps
19 reported severe mood swings, apathy, general malaise,
or depression
18 reported peripheral neuropathy, pain, cramps, tingling,
or numbness in their limbs
16 reported chronic or severe diarrhea
15 reported experiencing hypoglycemia or feeling fatigued,
shaky and weak
15 reported vertigo, dizziness, fainting, or lightheadedness
15 reported severe or repeated headaches
10 reported menstrual irregularities or severe menstrual
problems
8 reported chest pain
8 reported high blood pressure
7 reported nausea
7 reported increasing weight or failure to lose weight
As an example of a high-protein, carbohydrate-restricted
diet, Table 3 presents a nutrient analysis of the sample menus
for the three stages of the Atkins Diet as described in Dr.
Atkins’ New Diet Revolution (pp. 257–259).
Actual menus analyzed can be found in Appendix A of this report.
Table 3. Nutrient Analysis of Atkins Sample Diets
| Table
3. Nutrient Analysis of Atkins Sample Diets |
| |
Atkins Induction |
Atkins Weight Loss |
Atkins Maintenance |
Energy, kcal |
1759 |
1505 |
2173 |
| Protein, g (% energy) |
143 (33%) |
120 (32%) |
135 (25%) |
Carbohydrate, g (% energy) |
15 (3%) |
36 (10%) |
116 (22%) |
Fat, g (% energy) |
125 (64%) |
97 (58%) |
110 (45%) |
Alcohol, g (% energy) |
0 |
0 |
26 (8%) |
Saturated fat, g |
42 |
45 |
38 |
Cholesterol, mg |
886 |
885 |
834 |
Fiber, g |
2 |
7 |
18 |
Calcium, mg (% DV) |
373 (37%) |
952 (95%) |
1019 (102%) |
Iron, mg (% DV) |
15 (86%) |
10 (54%) |
13 (70%) |
Vitamin C (% DV) |
20 (33%) |
140 (234%) |
242 (404%) |
Vitamin A, RE (% DV) |
799 (80%) |
1525 (153%) |
2521 (252%) |
Folate, _g (% DV) |
143 (36%) |
268 (67%) |
584 (146%) |
Vitamin B-12, 5g (% DV) |
11 (191%) |
8 (132%) |
5 (80%) |
Thiamin, mg (% DV) |
0.7 (48%) |
1.1 (76%) |
1.0 (64%) |
(DV=daily value) |
|
|
|
The nutritional analysis shows that the sample menus do not
meet recommended dietary intakes for macronutrients. In addition
to very high protein content and low carbohydrate content,
the menus at all three stages are very high in saturated fat
(Daily Value is < 20 g) and cholesterol (DV < 300 mg)
and very low in fiber (DV > 25 g). In addition, these sample
menus do not reach daily values for iron. The induction menu
does not meet the daily values for calcium, vitamin C, vitamin
A, folate, and thiamin. The weight loss menu is low on calcium,
folate, and thiamin.
Discussion
Nutrient Composition
Our nutrient analysis agrees with other reports in noting
that high-protein diets typically skew nutritional intake
toward higher-than-recommended amounts of dietary cholesterol,
fat, saturated fat, and protein, and have very low levels
of fiber and some other protective dietary constituents. The
Nutrition Committee of the Council on Nutrition, Physical
Activity, and Metabolism of the American Heart Association
states, “High-protein diets are not recommended because
they restrict healthful foods that provide essential nutrients
and do not provide the variety of foods needed to adequately
meet nutritional needs. Individuals who follow these diets
are therefore at risk for compromised vitamin and mineral
intake, as well as potential cardiac, renal, bone, and liver
abnormalities overall.” 18
Common Health Concerns
Constipation was reported by 44 percent
of the registrants. One registrant reported severe problems
with constipation: “I frequently resorted to laxatives
and sometimes went two weeks without a bowel movement.”
In one study, 68 percent of subjects on a low-carbohydrate
diet reported problems with constipation.1
Carbohydrate-rich plant foods, including vegetables, fruits,
grains, and legumes, are the only sources of fiber in the
diet. High-protein, carbohydrate-restricted diets are typically
low in fiber, and, as a result, often lead to constipation.
In our nutrient analysis of the sample menus in Dr. Atkins’
New Diet Revolution, fiber content ranged from 2 grams per
day on the induction diet to 18 grams per day on the maintenance
diet. Institute of Medicine recommendations target fiber intake
at 14 grams per 1,000 kcals, which works out to 28 to 42 grams
per day for an average adult. Individuals consuming Atkins-like
diets generally fall far short of this healthy goal.
Loss of energy was reported by 40 percent
of registrants. One registrant noted feeling “exhausted,
dizzy, and nauseated before almost passing out on the fifth
day of the diet.” Another noted being “so weak
I can hardly function.” A third stated, “After
two weeks I felt terribly tired and ended the diet with a
donut binge session.”
Loss of energy would be expected on a carbohydrate-restricted
diet, because the preferred fuel for the body is carbohydrate
in the circulating form of glucose or the storage form of
glycogen. Muscles need glucose to do maximal effort work.19
Limiting carbohydrate intake requires the body to utilize
other fuels, such as fats, amino acids, and ketone bodies.
Conversion of these nutrients to useable fuels takes longer
than providing glucose from carbohydrates. For brain function
and high-intensity activities, these fuels are poor substitutes
for glucose. In addition, during the induction and maintenance
phases, recommended caloric intake (1,500 to 1,700 kcals)
is well below adult energy requirements.
Bad breath was reported by 40 percent of
the registrants. One registrant noted, “I was miserable
on this diet. I had no appetite, no energy, and a terrible
taste in my mouth all the time.” A second summed up
her statement with, “Bad breath, funny taste in mouth,
feeling lethargic...and this diet is good for you? My body
didn’t think so!”
Bad breath occurs on high-protein, carbohydrate-restricted
diets, especially during the induction and weight-loss phases,
when a ketotic state is achieved. Problems with bad breath
were reported in 63 percent of patients on such diets in a
study done at Duke University.1 When fatty acids
are the primary source of energy and carbohydrate is severely
restricted, part of the fat particle cannot be metabolized
and builds up in the fluids outside the cells. These particles
are converted to ketones (an “emergency” energy
source), and unused ketones are excreted in the urine and
expired air, resulting in acetone-smelling breath.16
Difficulty concentrating was reported by
29 percent of the registrants. One registrant described her
experience this way: “I felt horrible. I couldn’t
concentrate or focus and felt foggy all the time.” Another
stated, “I was only on the diet a short time and had
a vertigo attack. I have since been out of balance and have
a loss of concentration.”
The primary fuel for the brain and nervous system is carbohydrate
in the form of glucose. When carbohydrate or total food intake
is restricted (especially when such restriction is <40
g/day), there is little or no glucose available for the brain.
The brain cells can utilize ketone bodies for energy in an
emergency, such as starvation or severe carbohydrate restriction,20
but some individuals can still note the deficiency of glucose
available to the brain. Possible symptoms include difficulty
concentrating or light-headedness.
Kidney problems were reported by 19 percent
of registrants. Ten percent reported kidney stones, 1 percent
reported severe kidney infections, and 8 percent reported
reduced kidney function. One registrant reported, “I
have recurring kidney infections with elevated leukocytes
and blood in my urine. I have tender flanks and am currently
under a urologist’s care to find the cause of the blood
and the pain.” Another noted that he had three kidney
stone episodes in the four months he was on a high-protein,
carbohydrate-restricted diet. A person who experienced her
first kidney stone episode while on a high-protein diet stated,
“Even though I lost weight on the diet, if it’s
responsible for my experience with kidney stones, it’s
not worth it!”
High-protein diets in general (high-protein, low-carbohydrate
diets have not been studied specifically) are associated with
reduced kidney function. Over time, individuals who consume
very large amounts of animal protein risk a permanent and
significant reduction in kidney function. Harvard researchers
reported recently that high-protein diets were associated
with a significant decline in kidney function, based on observations
in 1,624 women participating in the Nurses’ Health Study.
The damage was found only in those who already had reduced
kidney function at the study’s outset, but more than
40 percent of adults over age 40 in the United States already
have reduced kidney function, which suggests that most people
who have renal problems are unaware of that fact and do not
realize that high-protein diets may put them at risk for further
deterioration.9,21
The American Academy of Family Physicians notes that high
animal protein intake is largely responsible for the high
prevalence of kidney stones in the United States and other
developed countries and recommends protein restriction for
the prevention of recurrent kidney stones.22 Protein
ingestion increases renal acid secretion and calcium resorption
from bone and reduces renal calcium resorption. In addition,
animal protein is a major dietary source of purines, the major
precursors of uric acid, which is an important factor in some
people who have a propensity to form kidney stones. When uric
acid builds up, especially in an acid environment, it can
precipitate in uric acid stone formers and decrease the solubility
of calcium oxalate, a problem for calcium stone formers.17,22
This situation is aggravated when the diet is both high in
protein and carbohydrate-restricted because ketone bodies
compete with uric acid for renal tubular excretion such that
uric acid levels can increase even more.23
Cardiovascular disease, including heart
attack, atrial fibrillation, coronary arteriosclerosis, and
high serum cholesterol, was reported by 33 percent of the
registrants. One registrant who had a heart scan that revealed
no plaque or occlusions prior to starting a high-fat, high-protein,
carbohydrate-restricted diet began experiencing angina after
two years on the diet. An angiogram performed at that time
showed a severe artery blockage; the registrant underwent
angioplasty and stent placement. He said, “I believe
the diet gave me heart disease.” Another described feeling
as if “someone [was] boxing my ears with a very strong
throbbing in my neck.” That registrant checked into
the emergency room to learn that she had a heart rate of 210,
which was slowed down with medication. She had developed atrial
fibrillation, a condition in which disorganized electrical
conduction in the atria (upper chambers of the heart) results
in ineffective pumping of blood.
Typical low-carbohydrate, high-protein diets are extremely
high in dietary cholesterol and saturated fat. The effect
of such diets on serum cholesterol concentrations is a subject
of ongoing research. However, 14 percent of registrants reported
high serum cholesterol concentrations. Moreover, two participants
in a Duke University study on low-carbohydrate diets dropped
out of the study because of elevated serum lipid levels (one
had an increase in LDL cholesterol from 182 mg/dl to 219 mg/dl
in four weeks; the second had an increase from 184 mg/dl to
283 mg/dl in three months). A third study participant developed
chest pain and was subsequently diagnosed with coronary heart
disease. Normal LDL values are typically described as less
than 100 mg/dl, with higher limits for some groups; some investigators
have called for lower limits. In 30 percent of the Duke University
study participants, LDL cholesterol increased by more than
10 percent. The investigators reported, “Perhaps the
biggest concern about the low-carbohydrate diet is that the
increase in fat intake will have detrimental effects on serum
lipid levels.”24
The potentially adverse effects of low-carbohydrate diets
have been studied by investigators for more than 20 years.
LaRosa,25 with the Lipid Research Clinics Trial
at the George Washington University School of Medicine, placed
24 men and women on a low-carbohydrate diet for eight weeks.
In contrast to many studies of low-carbohydrate diets, no
supplements (such as flax oil) were given. Average LDL (“bad”)
cholesterol increased by 23 mg/dl. Average HDL (“good”)
cholesterol fell by 2.9 mg/dl.
Other biochemical measures of heart disease risk may be affected.
Fatty diets in general (low-carbohydrate, high-fat diets have
not been tested) may pose additional cardiovascular risks,
including increased risk for cardiovascular events immediately
following a meal. A recent study showed that the consumption
of a high-fat meal (a ham and cheese sandwich, whole milk,
and ice cream) reduced systemic arterial compliance by 25
percent at three hours and 27 percent at six hours.26
Researchers with the Framingham Heart Study have become concerned
that users of high-protein, high-fat diets are at risk for
heart disease because frequent fatty meals increase levels
of two of the most atherogenic (plaque-promoting) fatty particles
in the blood stream: chylomicrons, which are the body’s
main fat-transporting particles; and free fatty acids, small
fat particles that move freely in the blood stream. The research
group has been studying the carotid arteries of women for
12 years; the carotid is a key artery in the neck that moves
blood from the heart to the brain. The women who have chosen
to consume a high-fat, carbohydrate-restricted diet have roughly
double the fatty deposits in their arteries as those on a
higher-carbohydrate, lower-fat diet, suggesting an increased
risk of stroke and heart disease (W. Castelli, personal communication,
2003).
The Southern Medical Journal reported the sudden
cardiac death of a female adolescent while using a high-protein,
carbohydrate-restricted diet.23 She had had abnormally
low levels of potassium in her bloodstream, and the report’s
authors suggested possible mechanisms by which the diet may
have contributed to the abnormality. Potassium, calcium, and
magnesium are all used by the body to neutralize acidity and
balance blood pH levels. When ketone bodies are produced in
a carbohydrate-restricted diet, metabolic acidosis results.
The ketone bodies are paired with one of these minerals before
being excreted in the urine. A prolonged ketotic state can
thus result in depletion of blood minerals.23 Mineral
losses may also be compounded by the use of laxatives or diuretics.
Low blood mineral levels can result in arrhythmias and even
cardiorespiratory arrest. The onset of arrhythmias that required
medical treatment were reported by 26 (6 percent) of the registrants.
Gallbladder problems were reported by 9
percent of registrants. In describing her experience with
high-protein, low-carbohydrate diets, a young registrant stated,
“All I ate was meat and lots of cheese…I ended
up having to have my gallbladder removed.” Her doctor
told her that her gallbladder problems were caused by a fatty
diet.
Risk of diseases of the gallbladder, including gallstones,
gallbladder inflammation, and cholestasis (a sludge-like build
up in the gallbladder), is increased with obesity, fasting,
and rapid weight loss. A low-fat diet is usually the dietary
treatment for acute gallbladder inflammation.16
The consumption of meaty diets has been shown to nearly double
the risk of gallstones as compared to vegetarian diets in
women.27 However, no studies have specifically
evaluated the risks of gallbladder disease among low-carbohydrate
dieters.
Gout was reported by 5 percent of registrants.
Gout is an excruciating type of arthritis characterized by
joint swelling and pain caused by the accumulation of uric
acid crystals in the joint fluid. The condition is associated
with meaty diets, among other nutritional factors. Fasting
can also precipitate an attack of gout.16 The risk
of gout among low-carbohydrate dieters is unknown.
Osteoporosis was reported by 3 percent of
the registrants. Elevated protein intake is known to encourage
urinary calcium losses and has been shown in cross-cultural
and prospective studies to increase risk of fracture.10,11
When carbohydrate is limited and a ketotic state is induced,
this effect is magnified by the metabolic acidosis produced.17
In a 2002 study of 10 healthy individuals put on a low-carbohydrate,
high-protein diet for six weeks under controlled conditions,
urinary calcium losses increased 55 percent (from 160 to 248
mg⁄d, P < 0.01).8 The researchers concluded
that the diet presents a marked acid load to the kidney, increases
the risk for kidney stones, and may increase the risk for
bone loss.
Diabetes was reported by 4 percent of the
registrants. One individual wrote that “her diabetes
worsened,” but what stopped her from continuing the
diet was “the flank pain and almost tea-colored urine.”
No long-term studies have evaluated the effect of low-carbohydrate,
high-protein diets on diabetes. However, studies of high-protein
diets in general (not specifically low-carbohydrate diets)
raise important concerns. Renal impairment and cardiovascular
disease are particularly common in diabetes. The use of diets
that may further tax the kidneys and reduce arterial compliance
is not recommended.
In individuals with diabetes, the principal strategies for
preventing or slowing impairment of renal function include
controlling blood glucose levels, blood pressure, and blood
lipid concentrations, and decreasing protein intake to low
normal levels. The beneficial effect of low-protein diets
in diabetic nephropathy has been confirmed in two recent meta-analyses,
with no adverse effects on the glycemic control.28
Popular books and news stories have encouraged individuals
to avoid carbohydrate-rich foods, suggesting that high-protein
foods will not stimulate insulin release. Contrary to this
popular myth, however, proteins stimulate insulin release,
just as carbohydrates do. Clinical studies indicate that beef
and cheese cause a larger insulin release than pasta, and
fish produces a larger insulin release than popcorn.29
Cancer diagnoses were reported by 4 percent
of registrants: 1 percent reported colorectal cancer, while
3 percent reported other cancers. No research studies have
evaluated cancer risk among individuals following low-carbohydrate
diets. However, research in general populations raises concerns
about the effects of diets based on frequent consumption of
meat and other fatty foods.
Colorectal cancer is one of the most common forms of cancer
and is among the leading causes of cancer-related mortality.
Long-term high intake of meat, particularly red meat, is associated
with significantly increased risk of colorectal cancer. Food,
Nutrition, and the Prevention of Cancer, a 1997 report
by the World Cancer Research Fund and the American Institute
for Cancer Research, reported that, based on available evidence,
diets high in red meat were considered probable contributors
to colorectal cancer risk.
Harvard studies including tens of thousands of women and
men have shown that regular meat consumption increases colon
cancer risk by roughly 300 percent.12,13 Proposed
mechanisms for the observed association include the effect
of dietary fat on bile acid secretion, the action of cholesterol
metabolites within the colonic lumen, and the carcinogenic
action of heterocyclic amines produced during the cooking
process, among others. In addition, high-protein diets are
typically low in dietary fiber. Fiber facilitates the movement
of wastes, including intralumenal carcinogens, out of the
digestive tract and promotes a biochemical environment within
the colon that appears to be protective against cancer.4
Similarly, the Journal of the National Cancer Institute
recently reported that the rate of breast cancer among premenopausal
women who ate the most animal (but not vegetable) fat was
one-third higher than that of women who ate the least animal
fat.6 A separate study from Cambridge University,
published in the Lancet, also linked diets high in saturated
fat to breast cancer.5
Limitations on Weight Loss
Despite media accounts of seemingly dramatic weight loss,
the effect of high-protein diets on body weight is similar
to that of other weight-reduction diets. Three recent studies—one
at Duke University,1 a second at the University
of Pennsylvania,2 and a third at a Philadelphia
medical center3—suggest that mean weight
loss with high-protein diets during the first six months of
use is approximately 20 pounds. Although this weight loss
is greater than that which occurs from eating plans not designed
for weight loss (e.g., diets based on the Food Guide Pyramid
or National Cholesterol Education Program guidelines), it
is not demonstrably greater than that which occurs with other
weight-loss regimens or with low-fat, vegetarian diets prescribed
without energy restrictions.30
A closer look at the two studies published in the New
England Journal of Medicine comparing low-carbohydrate
diets and conventional—that is, moderately low-fat (25–30%),
restricted-calorie—diets for weight loss in obese adult
subjects shows that weight loss over 6 to 12 months was minimal
on both types of diets. Weight loss amounted to about half
a pound per week at six months and one-fifth of a pound per
week at one year on the low-carbohydrate diet. Weight loss
was about one-quarter to one-fifth of a pound per week at
six months and about one-tenth of a pound per week at one
year on the conventional weight-loss diet.2,3
One of these studies lasted for a year, at which point the
difference in weight loss between the two groups was no longer
statistically significant.2 The short-term difference
in weight loss between the diets can be explained in both
studies by lower caloric intake for those on the low-carbohydrate
diet as compared to those on the conventional weight-loss
diets. This conclusion is consistent with a recent review
of 107 research studies on low-carbohydrate weight-loss diets,
which concluded that weight loss was associated with longer
diet duration and reduction of calories, but not with reduced
carbohydrate intake.31 Seven registrants reported
neither losing nor gaining weight while on a high-protein,
low-carbohydrate diet.
Limitations
The key limitation of this report is that adverse health
effects were self-reported and are not likely to have the
same prevalence in the general population. Data collection
was Web-based and no attempt was made to ensure a representative
sample. These registry reports do not establish a cause-and-effect
relationship between the use of high-protein, high-fat, carbohydrate-restricted
diets and health problems. Nonetheless, the serious nature
of the problems reported points to an urgent need for monitoring
the effects of such diets, as well as a need for studies on
the long-term risks of these diets.
Report compiled by Neal D. Barnard, M.D., and Amy Joy Lanou,
Ph.D.
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Appendix
The nutrient analysis in Table 3: Nutrient Analysis of Atkins
Sample Diets is based on the following sample menus, which
are described in Dr. Atkins’ New Diet Revolution.
Typical Induction Menu
Breakfast
Bacon, 4 slices
Coffee, decaf, 8 ounces
Scrambled eggs, 2
Lunch
Bacon cheeseburger, no bun:
(Bacon, 2 slices
American cheese, 1 ounce
Ground beef patty, 6 ounces)
Small tossed salad, no dressing
Seltzer water
Dinner
Shrimp cocktail, 3 ounces
Mustard, 1 teaspoon
Mayonnaise, 1 tablespoon
Clear consommé, 1 cup
T-bone steak, 6 ounces
Tossed salad
Russian dressing
Sugar-free Jell-O, 1 cup
Whipped cream, 1 tablespoon
Typical Ongoing Weight-Loss Menu
Breakfast
Western Omelet:
(Eggs, 2
Cheddar cheese, 2 ounces
Bell peppers, 1 tablespoon
Onion, 1 tablespoon
Ham bits, 1/10 cup
Butter, 1 tablespoon)
Tomato juice, 3 ounces
Crispbread, 1 carbo grams (1/4 slice)
Tea, decaf, 8 ounces
Lunch
Chef's salad with ham, cheese, and egg with zero-carb dressing
Iced herbal tea, 8 ounces
Dinner
Subway seafood salad, 1 item
Poached salmon, 6 ounces
Boiled cabbage, 2/3 cup
Strawberries, 1 cup
Cream, 4 tablespoons
Typical Maintenance Menu
Breakfast
Gruyere and spinach omelet:
(Eggs, 2
Gruyere cheese, 2 ounces
Spinach, 1 cup cooked
Butter, 1 tablespoon)
1 cantaloupe
Crispbread, 4 carbo grams (1 slice)
Coffee, decaf, 8 ounces
Lunch
Roast chicken, 6 ounces
Broccoli, 2/3 cup, steamed
Green salad
Creamy garlic dressing
Club soda
Dinner
French onion soup, 1 cup
Salad with tomato, onion, carrots
Oil and vinegar dressing
Asparagus, 1 cup
Baked potato, 1 small, with sour cream (2 tablespoons) and
chives
Veal chops, 1 serving
Fruit compote, 1 generous cup
Wine spritzer, 16 ounces
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