Cure and prevent diabetes mellitus with diet, not drugs
Part 5: The evidence that a low-carb, saturated fat diet better for diabetics
Since the adoption of a low-fat diet as "healthy" in the early 1980s, diabetics have been put on such diets. Nobody thought to actually test whether they worked, with the results we see now of rising diabetes and obesity throughout the Western world. However, there were more enlightened scientists who saw the way things were going. Despite the expense and difficulty getting funding for trials which would not be of commercial benefit to drug and food producers, tests have been conducted into low-carbohydrate, high fat diets in diabetes. They have demonstrated pretty convincingly that a high-fat diet is far healthier for diabetics than the conventional "five portions of fruit and vegetables a day" advice diabetics usually get.
Here is some of the evidence.
The evidence on this page is very recent. But this evidence is not new —
we really have known some of it for over a century (see
the story of William Banting
and the studies which followed. And there never has been any convincing
evidence that a fatty diet causes heart disease (see
The Cholesterol Myth
and Gary Taubes' article,
The Soft Science of Dietary Fat
)
In the 3 August 2002 edition of the
British Medical Journal
an editorial entitled "Prevention and cure of type 2 diabetes: Weight loss is
the key to controlling the diabetes epidemic" (
BMJ
2002;325:232-233), said just that. It is generally accepted that weight loss
is probably the best way to treat diabetics who, usually are overweight,
because:
a reduction in weight of 10kg (22 lbs):
Reduces Hba1c more than Metformin
Reduces diabetes-related deaths
Improves blood lipids, without drugs
Improves blood pressure, without drugs
The difficulty is to reduce weight without increasing the risk of a heart
attack or damaging arteries. So with that in mind here are two studies which do
just that — by reducing carbohydrates and increasing fats:
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Sharman MJ, Kraemer WJ, Love DM, Avery NG, Gomez AL, Scheett TP, Volek JS. A
ketogenic diet favorably affects serum biomarkers for cardiovascular disease in
normal-weight men.
J Nutr
2002; 132: 1879-85
Human Performance Laboratory, University of Connecticut, Storrs 06269-1110, USA.
Very low-carbohydrate (ketogenic) diets are popular yet little is known
regarding the effects on serum biomarkers for cardiovascular disease (CVD).
This study examined the effects of a 6-wk ketogenic diet on fasting and
postprandial serum biomarkers in 20 normal-weight, normolipidemic men.
Twelve men switched from their habitual diet (17% protein, 47% carbohydrate and
32% fat) to a ketogenic diet (30% protein, 8% carbohydrate and 61% fat) and
eight control subjects consumed their habitual diet for 6 wk. Fasting blood
lipids, insulin, LDL particle size, oxidized LDL and postprandial
triacylglycerol (TAG) and insulin responses to a fat-rich meal were determined
before and after treatment.
There were significant decreases in fasting serum TAG (-33%), postprandial
lipemia after a fat-rich meal (-29%), and fasting serum insulin concentrations
(-34%) after men consumed the ketogenic diet. Fasting serum total and LDL
cholesterol and oxidized LDL were unaffected and HDL cholesterol tended to
increase with the ketogenic diet (+11.5%; P = 0.066). In subjects with a
predominance of small LDL particles pattern B, there were significant increases
in mean and peak LDL particle diameter and the percentage of LDL-1 after the
ketogenic diet. There were no significant changes in blood lipids in the
control group. To our knowledge this is the first study to document the effects
of a ketogenic diet on fasting and postprandial CVD biomarkers independent of
weight loss. The results suggest that a short-term ketogenic diet does not have
a deleterious effect on CVD risk profile and may improve the lipid disorders
characteristic of atherogenic dyslipidemia.
COMMENT: with a diet in which 61% of calories came from fat, you might expect
that cholesterol, etc, would rise. In fact, it did just the opposite. The
figures are:
fasting serum triacylglycerol - 33%
postprandial lipaemia
- 29%
postprandial insulin
- 34%
HDL
+11.5%
Total cholesterol was unchanged
|
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Westman EC, Yancy WS, Edman JS, Tomlin KF, Perkins CE. Effect of 6-month
adherence to a very low carbohydrate diet program.
Am J Med
2002 Jul;113(1):30-6
Division of General Internal Medicine, Duke University, Durham, North Carolina
To determine the effect of a 6-month very low carbohydrate diet program on
body weight and other metabolic parameters. Fifty-one overweight or obese
healthy volunteers who wanted to lose weight were placed on a very low
carbohydrate diet (less than 25 grams per day), with no limit on total calorie
intake. They also received nutritional supplementation and recommendations
about exercise, and attended group meetings at a research clinic.
The outcomes were body weight, body mass index, percentage of body fat
(estimated by skinfold thickness), serum chemistry and lipid values, 24-hour
urine measurements, and subjective adverse effects.
Forty-one (80%) of the 51 subjects attended visits through 6 months. In these
subjects, the mean (+/- SD) body weight decreased 10.3% +/- 5.9% (P
<0.001) from baseline to 6 months (body weight reduction of 9.0 +/- 5.3 kg
and body mass index reduction of 3.2 +/- 1.9 kg/m(2)).
The mean percentage of body weight that was fat decreased 2.9% +/- 3.2% from
baseline to 6 months (P
<0.001).
The mean serum bicarbonate level decreased 2 +/- 2.4 mmol/L (P
<0.001) and blood urea nitrogen level increased 2 +/- 4 mg/dL (P <0.001).
Serum total cholesterol level decreased 11 +/- 26 mg/dL
(P = 0.006),
low-density lipoprotein cholesterol level decreased 10 +/- 25
mg/dL (P = 0.01),
triglyceride level decreased 56 +/- 45 mg/dL (P
<0.001),
high-density lipoprotein (HDL) cholesterol level increased 10 +/- 8 mg/dL (P
<0.001),
and the cholesterol/HDL cholesterol ratio decreased 0.9 +/- 0.6 units (P
<0.001).
There were no serious adverse effects
, but the possibility of adverse effects in the 10 subjects who did not adhere
to the program cannot be eliminated.
A very low carbohydrate diet program led to sustained weight loss during a
6-month period.
COMMENT:
Over the period of the diet, the participants lost an average of 21.3 pounds,
and showed a 6.1% drop in cholesterol, and almost a 40% drop in the level of
triglycerides in their blood. In addition, their HDL levels increased by about
7%. This is all good stuff.
In an interview for Reuters Health, the study's main author, Dr Eric Westman
said he was surprised that patients' cholesterol levels improved by the end
of six months as it was an unexpected a finding. "We were somewhat surprised to
find that patients' blood lipid profiles
improved, even though there was much more fat in the diet," he said. "We had
thought the fat in the diet would increase the cholesterol."
This statement disappoints me for it shows how little is read of the literature
on this subject. As long ago as 1930 the
Journal of Biological Chemistry
published the results of a trial conducted in Bellevue Hospital, New York, on
Dr Viljalmur Stefansson and Dr Karsten Anderson, who lived on an all-meat (with
its fat) diet for a year. As well as other benefits, their blood cholesterol
fell by 1.3 mmol/l (50mg/dl).
I do welcome, however, another quote from Dr Westman: "The diet lowers
cholesterol and triglycerides and raises HDL . . . which may
represent an entirely new approach to the control and prevention of heart
disease," They are starting to get the message.
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Dr James Hays initially presented his work with high fat diet at ENDO 99 in San
Diego, CA, and was censured for it (see below). Here, three years later, he has
clearly chosen a more "acceptable" approach
(i.e., the use of a drug with dietary modification). As his results without the
drug were very impressive, I wonder why he included drugs (research grant
perhaps?). Nevertheless, the figures show that his high-saturated fat diet had
much greater beneficial effects than the drugs.
NOTE:
Until now, studies into the effect of reducing carbohydrates in the diets of
diabetics have played safe and followed the party line that saturated fats are
harmful. This has meant that the fats used to replace starches have been
"beneficial" monounsaturated fats. In the study below, a starch-reduced,
saturated fatty diet is compared to one in which the fats were monounsaturated.
As you can see from this abstract, the effects from the saturated fats were
much better.
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Hays JH, Gorman RT, Shakir KM. Results of use of metformin and replacement of
starch with saturated fat in diets of patients with type 2 diabetes.
Endocr Pract
2002 May-Jun;8(3):177-83
ih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12113629&dopt=Abstract
Christiana Care Health Services, Inc., Cardiology Research, Newark, Delaware
19718, USA.
OBJECTIVE:
To improve glycemic control by substituting saturated fat for starch, to
identify any adverse effect on lipids masked by the extensive use of metformin
and lipid-lowering drugs, and to attempt to separate dietary effects from
effects of multiple drugs.
METHODS:
We undertook a retrospective review of medical records of patients who
completed 1 year of follow-up after dietary prescription. The study subjects
included 151 patients in the diet group (whose dietary instructions included
high saturated fat but starch avoidance
) and 132 historical control subjects (who were allowed unlimited
monounsaturated fat but had restriction of starch in their diets).
RESULTS:
Hemoglobin A1c (HbA1c) levels improved in both study groups (-1.4 +/- 0.2% [P
<0.001]; 95% confidence interval [CI], -1.9 to -0.9). Use of metformin was
associated with a decrease in HbA1c (
-0.12
+/- 0.003%/mo [P
<0.001]; 95% CI, -0.17 to -0.07). The diet group had an additional decrease
of
-0.7
+/- 0.2% (P
<0.001; 95% CI, -1.1 to -0.3).
Weight increase was associated with the use of insulin
(+0.3 +/- 0.07 kg/mo [P
<0.001]; 95% CI, 0.2 to 0.5), sulfonylurea (+0.18 +/- 0.06 kg/mo
[P<0.01]; 95%
CI, 0.05 to 0.30), and troglitazone (+0.7 +/- 0.2 kg/mo [P
<0.005]; 95% CI, 0.3
to 1.2). Although not statistically significant, metformin therapy showed a
trend for weight loss (-0.14 +/- 0.08 kg/mo; P = 0.07).
An additional weight loss was noted in the diet group
(
-2.65
+/- 0.62 kg [P
<0.001]; 95% CI, -3.87 to -1.44).
Hydroxymethylglutaryl-coenzyme A reductase inhibitor [statin] use was
associated with reduced total cholesterol level (
-1.7
+/- 0.6 mg/dL per month [P
<0.005]; 95% CI, -2.9 to -0.5). The diet group had an additional decrease of
-13.0
+/- 4.5 mg/dL (P
<0.001; 95% CI, -21.9 to -4.1).
No significant effect of the diet on triglyceride, low-density lipoprotein, or
high-density lipoprotein levels was detected.
CONCLUSION:
Addition of saturated fat and removal of starch from a high-monounsaturated
fat and starch-restricted diet improved glycemic control and were associated
with weight loss without detectable adverse effects on serum lipids.
COMMENT: 1. Diet reduced HbA1c by six times as much as drugs. 2. Diet reduced
weight where drugs had little effect. 3. The high-fat diet reduced total
cholesterol seven times as much as statins (the drug of choice).
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As more and more children are becoming increasingly overweight and also
developing Type 2 diabetes, weight reduction is increasingly important for them
as well. Never was it more true than in diabetes that prevention is better than
cure. The following study looks at reducing the weight and, thus, the
likelihood of contracting diabetes in children.
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Sondike S, Jacobson, Copperman. The ketogenic diet increases weight loss but
not cardiovascular risk: A randomized controlled trial.
J Adolescent Health Care
2000; 26: 91.
Schneider Children's Hospital in New Hyde Park, N.Y
This study was conducted on overweight children aged 12 to 18. They were
between 20 and 100 pounds overweight. The children were split into two groups.
One group ate a conventional low-fat, carbohydrate based "slimming" diet
composed of whole grains, fruits and vegetables with fat-free dairy products,
low-fat meats, poultry and fish. Their total intake was limited to 1,100
calories per day. The other group ate a high-fat, low-carb diet in which they
were allowed to eat as many calories as they wanted in the form of untrimmed
meat, cheese, eggs, poultry and fish. Their carbohydrates came from two salads
a day and minimal other carbs.
RESULTS
Despite consuming on average 66% more calories per day, after 12 weeks the
children consuming the low-carbohydrate diet lost more weight than those
following the low-fat, high-carb plan:
|
|
Low-carb
|
Low-fat
|
|
Calorie intake
|
1830
|
1100
|
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Weight loss
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19 lbs
|
8.5 lbs
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HDL
|
Increased
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Decreased
|
|
Triglycerides
|
-52%
|
-10%
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As high-protein/fat diets are thought to have adverse effects on kidneys and
liver, kidney and liver functions were regularly monitored. They were found to
be unaffected by this diet.
COMMENT:
Six to twelve months later, most of the low-carb dieters had maintained their
new lower weight. This study provides additional evidence for the efficacy of a
low-carb weight loss programme specifically for the most vulnerable group
— teenagers.
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The study above was not the first to show that low-calorie diets are not the
best for weight loss. In 1997 a study concluded that such diets actually
increased weight. Its authors concluded that: "Reduced fat and calorie intake
and frequent use of low-calorie food products have been associated with a
paradoxical increase in the prevalence of obesity" (Heini AF, Weinsier RL.
Divergent trends in obesity and fat intake patterns:
the American paradox.
Am J Med
1997; 102: 259-64)
In the following report, Dr James Hays, an endocrinologist and Director of the
Limestone Medical Center, Wilmington, DE, presented the results of three
studies using a "very high fat diet" on diabetics. It is reported that his
submission did not meet with favour with the other delegates. Such a reaction
is very common whenever anyone bucks the trend.
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Hays J.Paper presented to the 81st Annual Meeting of the Endocrine Society, 15
June1999.
"A very high-fat, low-carbohydrate diet has been shown to have astounding
effects in helping type 2 diabetics lose weight and improve their blood lipid
profiles."
Report of three studies of men and women with Type 2 diabetes involving very
high-fat, low-carbohydrate diet to measure ite effect on body mass index (BMI),
triglycerides, HDL, LDL and HbA1c.
METHODS.
A diet with unlimited meat and cheese; carbohydrates restricted to eating
unprocessed foods, mainly fresh fruit and vegetables. At least 50% of calories
from fat, of which 90% was saturated and 10% monounsaturated; no more than 20%
of calories from carbohydrates.
RESULTS.
After 12 months:
Total cholesterol declined from 231 to 190 mg/dl
LDL (the 'bad' cholesterol) fell from 133 to 105 mg/dl,
HDL (the 'good' cholesterol) increased from 44 to 47 mg/dl.
Triglycerides declined from 229 to 182 mg/dl.
HbA1c, which at the start of the study averaged 3.34 percent above normal,
declined to just 0.96 percent above normal
Average weight loss was in the order of 40 pounds.
By the end of the one-year study 90 percent of the patients had achieved ADA
(American Diabetes Association) targets for HbA1c, HDL, LDL and triglycerides.
CONCLUSION
"If you have a diet that results in weight loss,
lower cholesterol, and a better lipid profile,
eventually everybody will be eating that way.
It's going to come whether we like it or not."
COMMENT: I couldn't agree more!
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This is one of the earliest trials which looked at increasing dietary fats at
the expense of carbohydrates. Because it was not politically correct to raise
fats (they raise cholesterol levels, don't they?), fats were only raised to a
modest 45%. Nevertheless there was a noticeable benefit, and it was a start.
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Garg A, Bantle JP, Henry RR, Coulston AM, Griver KA, Raatz SK, Brinkley L, Chen
YD, Grundy SM, Huet BA, et al Effects of varying carbohydrate content of diet
in patients with non-insulin-dependent diabetes mellitus.
JAMA
1994; 271: 1421-8
Center for Human Nutrition, University of Texas Southwestern Medical Center at
Dallas 75235-9052.
OBJECTIVE
— To study effects of variation in carbohydrate content of diet on
glycemia and
plasma lipoproteins in patients with non-insulin-dependent diabetes mellitus
(TYPE-2).
DESIGN
— A four-center randomized crossover trial.
SETTING
—Outpatient and inpatient evaluation in metabolic units.
PATIENTS
—Forty-two TYPE-2 patients receiving glipizide therapy.
INTERVENTIONS
—A high-carbohydrate diet containing 55% of the total energy as
carbohydrates
and 30% as fats was compared with a high-monounsaturated-fat diet containing
40% carbohydrates and 45% fats. The amounts of saturated fats, polyunsaturated
fats, cholesterol, sucrose, and protein were similar. The study diets, prepared
in metabolic kitchens, were provided as the sole nutrients to subjects for 6
weeks each. To assess longer-term effects, a subgroup of 21 patients continued
the diet they received second for an additional 8 weeks.
MAIN OUTCOME MEASURES
— Fasting plasma glucose, insulin, lipoproteins, and glycosylated
hemoglobin
concentrations. Twenty-four-hour profiles of glucose, insulin, and triglyceride
levels.
RESULTS
— The site of study as well as the diet order did not affect the results.
Compared with the high-monounsaturated-fat diet, the high-carbohydrate diet
increased fasting plasma triglyceride levels and very low-density lipoprotein
cholesterol levels by 24% (P
< .0001) and 23% (P = .0001), respectively, and increased daylong plasma triglyceride, glucose, and insulin values by 10% (P = .03), 12% (P < .0001), and 9% (P = .02), respectively. Plasma total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels remained unchanged. The effects of both diets on plasma glucose, insulin, and triglyceride levels persisted for 14 weeks.
CONCLUSIONS
— In TYPE-2 patients, high-carbohydrate diets compared with
high-monounsaturated-fat diets caused persistent deterioration of glycemic
control and accentuation of hyperinsulinemia, as well as increased plasma
triglyceride and very-low-density lipoprotein cholesterol levels, which may not
be desirable.
COMMENT:
This study showed that a higher-fat diet was better than the usual
high-carbohydrate diets.
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Pregnant women are more susceptible to a form of diabetes called "gestational
diabetes". As the following study demonstrates, this condition also benefits
from a low-carbohydrate diet
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Major CA, Henry MJ, De Veciana M, Morgan MA. The effects of carbohydrate
restriction in patients with diet-controlled gestational diabetes.
Obstet Gynecol
1998 Apr;91(4):600-4
University of California, Irvine Medical Center, Department of Obstetrics and
Gynecology, Orange 92686, USA.
OBJECTIVE:
To determine the effect of carbohydrate restriction on perinatal
outcome in patients with diet-controlled gestational diabetes mellitus (GDM).
METHODS:
Women with diet-controlled GDM were divided non-randomly into two
groups based on their dietary carbohydrate content: those with low dietary
carbohydrate content (below 42%) and those with high dietary carbohydrate
content (exceeding 45%). Subjects kept dietary accounts and were followed with
daily fasting and postprandial glucose assessments. Subjects also were tested
daily for urinary ketones. Glycosylated hemoglobin, mean fasting and
postprandial glucose values, incidence of macrosomia and large for gestational
age (LGA) infants, cesarean deliveries for cephalopelvic disproportion and
macrosomia, and need for insulin therapy were compared between the groups.
RESULTS:
The two groups were identical in terms of demographic characteristics.
Significant reductions in the postprandial glucose values were seen among
subjects in the low-carbohydrate group. Fewer subjects in the low-carbohydrate
group required the addition of insulin for glucose control (P
< .047; relative risk [RR] 0.14; 95% confidence interval [CI] 0.02, 1.00). The incidence of LGA infants was significantly lower in the low-carbohydrate group (P < .035; RR 0.22; 95% CI 0.05, 0.91). Subjects in the low carbohydrate group also had a lower rate of cesarean deliveries for cephalopelvic disproportion and macrosomia (P < .037; RR 0.15; 95% CI 0.04, 0.94).
CONCLUSION:
Carbohydrate restriction in patients with diet-controlled GDM results in
improved glycemic control, less need for insulin therapy, a decrease in the
incidence LGA infants, and a decrease in cesarean deliveries for cephalopelvic
disproportion and macrosomia.
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Diabetic patients often find themselves in hospital. Many of them will be
maintained on a special formula diet. The common feed in this case is one high
in the carbohydrate, glucose. In the following study, this was replaced with a
low-carbohydrate, high-fat feed with 50% of calories as fat. As you can see,
the low-carb feed was better for diabetic patients.
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Sanz-Paris A, Calvo L, Guallard A, Salazar I, Albero R. High-fat versus
high-carbohydrate enteral formulae: effect on blood glucose, C-peptide, and
ketones in patients with type 2 diabetes treated with insulin or sulfonylurea.
Nutrition
1998 Nov-Dec;14(11-12):840-5
Endocrinology and Nutrition Unit, Miguel Servet Hospital, Zaragoza, Spain.
Recently, two commercial enteral formulae for diabetic patients have been made
available in Spain: a high-complex-carbohydrate, low-fat formulation (HCF) and
a low-carbohydrate formulation (RCF). This study compares the effects of the
two enteral nutritional formulae in patients with non-insulin-dependent
diabetes mellitus (type 2 diabetes) treated with sulfonylurea or insulin.
Fifty-two type 2 diabetes patients were randomly assigned to receive one of the
two enteral formulae. Test enteral formula breakfast (250 cc) were consumed at
approximately 0900 h after routine medications (insulin or oral agents) had
been taken. Venous blood samples were obtained during fasting, before
medication, and at 30 and 120 min after the start of the meal.
The glycemic
response of patients to the HCF was significantly greater than to RCF, but
lower than in the sulfonyl type 2 diabetes treated groups.
The incremental
glucose response was within acceptable levels except in insulin treatment type
2 diabetes patients given HCF.
Glucose, insulin, and C-peptide responses were
higher in HCF than RCF groups.
Two-factor analysis of variance on mean
increments of blood glucose and C-peptide from basal levels to 30 min show the
type of enteral nutrition as the main factor (P = 0.0010 and P = 0.0005,
respectively).
The RCF formula supplies 50.0% of energy as fat and 33.3% as
carbohydrates, so it may be a ketogenic diet. It was found that both ketone
bodies were higher after RCF than after HCF ingestion, but without statistical
significance.
We conclude that the partial replacement of complex digestible
carbohydrates with monounsaturated fatty acids in the enteral formulae for
supplementation of oral diet may improve glycemic control in patients with type
2 diabetes. The long-term effects of enteral diets high in monounsaturated
fatty acids need further evaluation in patients with type 2 diabetes.
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This is another of the early studies which replaced carbs with monounsaturated
fat, this time from Australia where they are as cholesterolphobic as the
Americans. As consequence, fats are only raised from 24% to 38% of calories. I
would still class this as a low-fat diet, nevertheless, even with this small
increase in fat, there was a noticeable improvement and, if nothing else the
diet would be considerably more palatable.
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Campbell LV, Marmot PE, Dyer JA, Borkman M, Storlien LH. The
high-monounsaturated fat diet as a practical alternative for TYPE-2.
Diabetes Care
1994 Mar;17(3):177-82
Diabetes Centre, St. Vincent's Hospital, Camperdown, Sydney, New South Wales,
Australia.
OBJECTIVE
— To examine the dietary preferences of and metabolic effects in
patients with non-insulin-dependent diabetes mellitus (TYPE-2) of a
home-prepared high-monounsaturated fat (HM) diet compared with the recommended
high-carbohydrate (CHO) diet.
RESEARCH DESIGN AND METHODS
— Ten men with mild TYPE-2 prepared HM and high-CHO
diets at home alternately and in random order for 2 weeks each with a minimum
1-week washout. Before and after each diet, 24-h urine glucose, fasting lipids,
fructosamine, and 6-h profiles of glucose, insulin, and triglycerides were
measured. Dietary preferences were assessed by questionnaire.
RESULTS
— In the HM diet, patients consumed 40% of energy intake as CHO and 38%
as fat (21% monounsaturated) compared with 52 and 24%, respectively, in the
high-CHO diet, with equal dietary fiber content. Body weight and total energy
intake were similar in both. The HM diet resulted in significantly lower 24-h
urinary glucose excretion, fasting triglyceride, and mean profile glucose
levels. The fructosamine levels, the fasting total, low-density lipoprotein,
and high-density lipoprotein cholesterol, and the prandial triglyceride
concentrations did not differ significantly as a result of the diets. The two
diets did not differ in ratings for overall acceptance, taste, cost, ease of
preparation, variety, or satiety.
CONCLUSIONS
— Prepared at home, the HM diet was, in the short-term,
metabolically better in some aspects than the currently recommended diet for
TYPE-2. It also provided a palatable alternative.
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People are told to increase their intakes of fibre to prevent diabetes.
Diabetics are told to eat bran and wholemeal cereal products as part of their
treatment. Low carbohydrate diets usually reduce the amount of fibre eaten. So
does that matter? I don't believe so and this study lends weight to that belief
as it shows just how little evidence there is for this recommendation.
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Marshall JA, Weiss NS, Hamman RF. The role of dietary fiber in the etiology of
non-insulin-dependent diabetes mellitus. The San Luis Valley Diabetes Study.
Ann Epidemiol
1993 Jan;3(1):18-26
Department of Preventive Medicine and Biometrics, University of Colorado
Health Sciences Center, Denver 80262.
To investigate the hypothesis that a low intake of dietary fiber could increase
the risk of developing non-insulin-dependent diabetes mellitus (NIDDM), we
ascertained prior dietary intake of 242 persons with known diabetes and 460
persons without a prior diagnosis of diabetes among 20- to 74-year-old
residents of two counties in southern Colorado from 1984 to 1986.
When persons
with diabetes were compared to nondiabetic controls, a higher reported fiber
intake prior to diagnosis was found among persons with diabetes. A decrease in
fiber of 10 g/d was associated with a decrease in risk of NIDDM of 0.75 (95%
confidence interval: 0.59 to 0.96), rather than an increase as hypothesized.
However, when the diabetic group was limited to those with diabetes for less
than 5 years, this association was no longer present. Two further analyses were
carried out on 1317 persons without a prior diagnosis of diabetes seen between
1984 and 1988. Among these persons, current fiber intake was inversely
associated with fasting plasma insulin concentration. However, fiber explained
less than 1% of the variation in fasting insulin levels.
When persons with
previously undiagnosed NIDDM were compared to normal controls, the odds ratio
relating a decrease in fiber consumption of 10 g/d to NIDDM was 1.21 (95%
confidence interval: 0.70 to 2.10) adjusting for calorie and carbohydrate
intake.
All analyses were adjusted for age, sex, ethnicity, and body mass
index.
The inconsistent findings reported here do not support the hypothesis
that increasing dietary fiber intake could reduce the future occurrence of
NIDDM.
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Here is another early study which demonstrates that cholesterol and other "risk
factors" for heart disease in diabetics is lessened by increasing the fat
content of their diets and reducing the carbs.
|
Garg A, Grundy SM, Unger RH. Comparison of effects of high and low carbohydrate
diets on plasma lipoproteins and insulin sensitivity in patients with mild
NIDDM.
Diabetes
1992 Oct;41(10):1278-85
Veterans Affairs Medical Center, University of Texas Southwestern Medical
Center, Dallas 75235-9052.
Previous studies indicate that diets rich in digestible carbohydrates improve
glucose tolerance in nondiabetic individuals, but may worsen glycemic control
in NIDDM patients with moderately severe hyperglycemia. The effects of such
high-carbohydrate diets on glucose metabolism in patients with mild NIDDM have
not been studied adequately.
This study compares responses to an isocaloric
high-carbohydrate diet (60% of total energy from carbohydrates) and a
low-carbohydrate diet (35% of total energy from carbohydrates) in 8 men with
mild NIDDM. Both diets were low in saturated fatty acids, whereas the
low-carbohydrate diet was rich in monounsaturated fatty acids.
The two diets
were matched for dietary fiber content (25 g/day).
All patients were randomly
assigned to receive first one and then the other diet, each for a period of 21
days, in a metabolic ward.
Compared with the low-carbohydrate diet, the
high-carbohydrate diet caused a 27.5% increase in plasma triglycerides and a
similar increase in VLDL-cholesterol levels; it also reduced levels of HDL
cholesterol by 11%.
Plasma glucose and insulin responses to identical standard
breakfast meals were studied on days 4 and 21 of each period, and these did not
differ significantly between the two diets. At the end of each period, a
euglycemic hyperinsulinemic glucose clamp study with simultaneous infusion of
[3-3H]glucose revealed no significant changes in hepatic insulin sensitivity;
and peripheral insulin-mediated glucose disposal remained unchanged (14.7 +/-
1.4 vs. 16.5 +/- 2.3 microM.kg-1.min-1 on the high-carbohydrate and
low-carbohydrate diets, respectively).
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See also
an abstract from the Journal of the American College of Cardiology
In which the past President of the College says that the current dietary
guidelines are the cause of diabetes and states that their defence is no longer
tenable.
Now, for practical advice on the correct way of eating to both lose weight and
effectively treat diabetes, go to
Part 6
.
Introduction
Part 1: The scale of the problem
Part 2: What is diabetes -- Are you at risk?
Part 3: Conventional treatment for Type-2 diabetes – and why it fails
Part 4: Why carbs are the wrong foods for diabetics
Part 5: The evidence
Part 6: The correct diet for a Type-2 diabetic, (or treatment without drugs)
Part 7: Treatment for Type-1 diabetes
Suitable foods for diabetics
Last updated 6 February 2008
another website,
Diabetes Diet spells out in easy to read terms just what causes diabetes and how best to treat diabetes.
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