, Mohd-Yusof Barakatun-Nisak,
Nutrition therapy is keystone of diabetes prevention and management and its impor-
tance has long been recognized before the era of modern scientific medicine.
known as the Allen diet, was commonly used to treat diabetes.
Another diet with
mately 70% was used by Elliot P. Joslin for managing diabetes in the 1920s.
betes (T2D), those eccentric diets were remarkably successful in managing diabetes
and for even keeping patients with type 1 diabetes alive for a few years.
diabetes was commonly defined as carbohydrate-intolerance disease.
maximum of 35% to 40% of the total daily caloric intake. By the late 1970s, a strong
claim to reduce total fat and dietary saturated fat (SFAs) intake was made due to
increased incidence of cardiovascular death, particularly in patients with diabetes.
Reduction of fat intake by approximately 10% required a compensatory increase in
Astra Zeneca Inc, and Boeringher Inglehiem Inc, and is a consultant to Merck Inc. B.-N. Yusof
has nothing to disclose.
Department of Endocrinology, Joslin Diabetes Center, Harvard Medical School, One Joslin
Joslin Diabetes Center, Harvard Medical School, Boston, MA
Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences,
* Corresponding author.
Medical nutrition therapy Nutrition Diet Glycemic index Diabetes
Medical nutrition therapy is effective in improving glycemic control, promoting weight loss,
and modifying cardiovascular risk factors in patients with diabetes.
Reduction of carbohydrate load, selection of low glycemic index food, and balancing
macronutrients improve postprandial blood glucose levels.
Selection of healthful dietary patterns, such as the Mediterranean diet or DASH diet, are
beneficial in managing diabetes.
Endocrinol Metab Clin N Am 45 (2016) 799–817
ª 2016 Elsevier Inc. All rights reserved.
approximately 55% to 60% (
contributing factor to poor diabetes control and weight gain, little has changed for
the past 3 decades.
Recently, the importance of specific foods and overall dietary
lar diseases (CVD) has emerged.
This review article discusses the current evidence
MEDICAL NUTRITION THERAPY FOR DIABETES MANAGEMENT
In 1994, the American Dietetic Association used the term “medical nutrition therapy”
(MNT) to better articulate appropriate nutrition care and process in diabetes manage-
MNT can be described as intensive, focused, and structured nutrition therapy
progress in pharmacologic management of diabetes, MNT remains a crucial tool for
achieving optimal glycemic control.
Although MNT is widely recognized by major diabetes organizations across the
prime goal of MNT is to attain and maintain optimal glycemic control and metabolic
improvement through healthy food choices while considering patients’ personal
needs, preferences, and lifestyle patterns.
Proper MNT was shown to reduce A1C
MNT was also shown to be particularly beneficial after initial diabetes diag-
nosis and in patients with poor glycemic control. Nevertheless, its effectiveness is
evident at any A1C level across the entire course of the disease.
Practically, MNT remains the most challenging component of diabetes self-
MNT should be provided by registered dietitians or by health care providers who
are well versed in nutrition. Comprehensive evaluation of the individual eating pattern,
needs, nutrition status, weight history, and history of previous nutrition education are
required before recommending an MNT plan.
Fig. 1. Trend in macronutrient intake among adults with diabetes in the United States be-
nutrient intake among adults with diabetes in the United States: 1988-2004. J Am Diet Assoc
Hamdy & Barakatun-Nisak
A comparison of key recommendation of medical nutrition therapy for people with type 2
intake to promote
weight loss in
Recommend reduce daily
caloric intake between
250 and 500 calories for
replacement that matches
the nutrition guideline
can be used to initiate and
maintain weight loss.
20%–35% total fat
protein, and <35% total
fat with adjustment
should be made to meet
the cultural and food
preference of individual.
variety of eating
Recommend a variety
of dietary patterns
intake from whole
and dairy products
with emphasis on
foods lower in
Recommend food with
a low GI value.
Recommend foods with a
low GI value, such as
whole grains, legumes,
fruits, green salad with
olive oil–based dressing
and most vegetables.
of refined carbohydrates,
processed grains, and
starchy foods, especially
most pastas, white bread,
white rice, low-fiber
cereal, and white
Emphasis on foods
with higher fiber.
population (25–50 g
per day or 15–25 per
w14 g fiber/
1000 calories (20–35 g) per
day. If tolerated,
hyperglycemia and should
intake of sucrose-
and to avoid
Added sugar can be
substituted for other
mixed meals up to
maximum of 10%
total caloric intake.
Recommend to limit
consumption of sugar and
(continued on next page)
Nutrition in Diabetes
intake below daily
0.8 g/kg body
diabetes or kidney
Recommend as for
(1.0–1.5 g/kg body
0.8 g kg/body weight
for those with
of not <1.2 g/kg of
adjusted body weight
patients. Patients with
signs of kidney disease
should get a consult from
increasing protein intake.
Protein can be modified
but not lowered to a level
that may increase the risk
of malnutrition or
of total fat, SFA,
transfat as for the
fat between 20%
plan with key
element of a
style diet over low
in total fat and
food rich in long-
chain omega 3
fatty acids but no
restriction to <7%
and limit transfat to
a minimum level.
Encourage food rich
in MUFA and PUFA
up to 20% and 10%,
Emphasis on quality of fat
rather than quantity.
Recommend SFA to <7%
and limit foods high in
transfats. PUFA and MUFA
should comprise the rest
of fat intake.
No support for
No support for routine
vitamin and mineral
No support for routine
vitamin and mineral
increase the risk
Advised as per general
consideration on the
Advise for moderate
consumed, no more than
for women and
day for men.
(continued on next page)
There is no final or conclusive evidence for an ideal macronutrient proportion for all pa-
tients with T2D, but rather there is an emphasis on individualization of eating plan (see
for overweight and obese patients with T2D provide some specific macronutrient dis-
tribution. Both point to the prime importance of macronutrient composition in a dia-
betes nutrition plan because carbohydrates, proteins, and fat have differential
impact on blood glucose levels.
They recommended reduction in the total glycemic load (GL) of carbohydrates and
their glycemic index (GI) (see
reducing carbohydrates in a diabetes diet.
Meanwhile, a recent randomized
calorie-restricted low-carbohydrate and high-carbohydrate diets at 24 and 52 weeks,
but a low-carbohydrate diet, which was also high in unsaturated fat and low in satu-
rated fat, achieved greater improvements in the lipid profile, blood glucose stability,
and reductions in diabetes medications, suggesting it as an effective strategy for
the optimizing T2D management.
Lowering GL by modest restriction of total carbo-
carbohydrates of lower GI also showed better effect on blood glucose levels in pa-
tients with T2D in comparison with conventional high-carbohydrate meal plans.
grains, which also improve overall diet quality.
Increased dietary fiber intake has been strongly recommended as part of diabetes
increasing gastrointestinal transit
Approximately 14 g of fiber per 1000
mately 50 g fiber per day, if tolerated, is effective in improving postprandial hyperglyce-
and legumes, is preferred, but if needed, fiber supplement, such as psyllium, resistant
b-glucan can be added to reach the total dietary fiber requirement.
Limiting added sugars has been consistently recommended by most organizations
(<2300 mg/d) with
is to be
No specific cutoffs
DASH eating plan.
Recommend <2300 mg (
tsp of salt) per day.
Dietary Approach to Stop Hypertension; GI, glycemic index; MUFA, monounsaturated fatty acids;
PUFA, polyunsaturated fatty acids; SFA, saturated fatty acids.
Adjusted body weight
1 drink is equal to 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of 80-proof
Nutrition in Diabetes
sensitivity, and de novo lipogenesis, in particular among overweight and obese pa-
The use of non-nutritive sweeteners may provide short-term benefits, but
clear that putting a limit on total fat (eg, <30%) and dietary cholesterol (<300 mg/d)
have no substantial benefit on cardiovascular risk. This is in line with the recent recom-
mendations of the Dietary Guideline for Americans,
American Diabetes Associa-
and American Heart Association.
Although these organizations strongly
support reduction in transfat from industrial hydrogenation of oils, the extent to which
dietary saturated fatty acids (SFAs) increase CVD risk has become a controversial
issue. Recent meta-analyses performed by De Sauza and colleagues,
ciations between dietary SFAs and all-cause mortality, CVD mortality, ischemic
stroke, or T2D. Interestingly, O’Sullivan and colleagues
observed that food high in
ciated with increased risk of mortality.
Increased consumption of fatty fish and long-chain omega 3 polyunsaturated fatty
acids (PUFA) from vegetable oils (eg, canola, corn) and walnut were found to be pro-
tective against CVD mortality in patients with T2D. They improve lipid profile and
modify platelet aggregation despite their lack of effect on glycemic control.
mendations do not support protein restriction for adults with T2D.
diabetes, especially when they are poorly controlled, lose significant amount of their
lean muscle mass as they age, and they lose it at a faster pace than individuals without
speeds lean muscle loss and may lead to profound sarcopenia.
ded dietary allowance of 0.8 g/kg per day for patients with diabetic kidney disease
who are not on dialysis.
In the Modification of Diet in Renal Disease (MDRD) study, assignment to a low-
protein diet of approximately 0.6 g/kg per day compared with the average protein
diet of approximately 1.3 g/kg per day in patients with advanced kidney disease did
not prevent the progressive decline in glomerular filtration rate (GFR) over 3 years.
Early findings from a meta-analysis of randomized clinical studies also did not show
However, this is contradicted by another recent meta-analysis by Nezu and col-
In the latter study, which has several limitations that may affect its quality, the
For patients on a hypocaloric weight reduction diet, increasing absolute protein
requirement in a hypocaloric diet may cause inadequate protein intake and put pa-
tients at risk of protein malnutrition and significant lean muscle mass loss during
weight reduction. Joslin guidelines advocate a daily protein intake of not less than
1.2 g/kg of adjusted body weight, which is approximately equivalent to 20% to 30%
A higher protein intake reduces hunger, improves satiety, and
tation to recommend for patients with diabetes except for those with suspected defi-
However, nutrient adequacy is important and should be achieved through a
ciated with micronutrient deficiencies.
There are specific patients with diabetes who
individuals, vegetarians, and pregnant and lactating women.
Low serum vitamin D, measured as serum 25-hydroxy vitamin D, is common among
including patients with diabetes.
Vitamin D may modify
diabetes risk through its effect on glucose homeostasis.
Longitudinal studies have
and A1C level.
Low serum vitamin D concentration was shown to be associated
with increased risk of macrovascular and microvascular complications in patients
However, recent systematic review and meta-analyses that included 35
supplementation did not show any beneficial
Patients who selected to have gastric bypass surgery for weight reduction are
particularly at higher risk for vitamin and mineral deficiencies postsurgery.
acid, to have anemia, and to have a high level of parathyroid hormone, indicating a
low level of vitamin D.
and after bariatric surgery for potential micronutrient deficiencies and supplement
them with iron, vitamin B12, folic acid, and vitamin D in addition to adequate protein
Diabetes-specific nutrition formula (DSNF) is
usually used as part of MNT to facilitate initial weight reduction while improving glyce-
DSNFs provide approximately 190 to 350 calories per serving. They
fortified with vitamins and minerals. As these products are specifically designed for
patients with diabetes, they contain low GI/GL carbohydrates, higher whey protein
than casein, and contain unique blends of amino acids.
This combination has
response than standard formulas. In a meta-analysis by Elia and colleagues,
DSNF lowered postprandial plasma glucose by 18.5 mg/dL, reduced peak glucose
with standard formulas. Attenuating postprandial plasma glucose excursion is always
a major clinical challenge and was found to contribute to cardiovascular complication
in patients with diabetes.
DSNF also improves glucagonlike peptide-1 (GLP-1) secretion. In response to food,
GLP-1 hormone plays an important role in glucose homeostasis through stimulating
Using DSNFs for tube feeding in hospitalized patients with diabetes was found to
the overall hospital cost in comparison with standard formulas.
As DSNFs are
tients with T2D, especially for elderly patients, was found to improve overall nutritional
status and optimize diabetes control.
Dietary pattern is an overall combination of beneficial foods that are
habitually consumed, which together produce synergistic health effects.
products, and vegetable oils and low in red meat, processed red meat, refined grains,
salt, and added sugar (
tioxidants, minerals, polyphenols, and unsaturated fatty acids and is lower in GI/GL,
sodium, and transfat.
examined 20 RCTs that investigated the effect of different
T2D for 6 months or more. Six dietary patterns were included in this analysis: low
carbohydrates, low GI, high fiber, high protein, vegetarian/vegan, and Mediterranean
dietary patterns in comparison with the commonly used diabetes nutrition guide-
Low carbohydrates, low-GI, high-protein, and Mediterranean dietary patterns
glycemic control was achieved with the Mediterranean dietary pattern (
etary pattern reduced A1C by 0.30% to 0.47%.
The Mediterranean dietary pattern
the subgroup of participants with T2D who followed a Mediterranean diet, even
without caloric restriction, had a lower incidence of CVD after a median duration of
4.8 years when compared with those who followed a low-fat diet.
changes in cardio-metabolic risk factors, improve insulin sensitivity, and reduce
oxidation and inflammation.
Such CVD benefits were not seen in the Women’s
tients with T2D.
The Dietary Approaches to Stop Hypertension (DASH) may be an ideal cardio-
protective dietary pattern for patients with T2D.
Although the benefits of the DASH
little research was done in patients with T2D. In an 8-week small RCT of 44 partici-
pants withT2D, the DASH diet significantly improved glycemic control and cardio-
metabolic parameters, and reduced inflammation markers.
Dietary quality also
Their consumption of some minerals (calcium and potassium), fiber, fruits, vegetables,
dairy, and whole grains were significantly increased.
Vegetarian or vegan diets have also been tested in patients with diabetes. A recent
5 225) found a significant reduction in A1C by an average of 0.39%, but with no ef-
However, this beneficial effect is difficult to separate
dietary fat, or changed diabetes medications.
SPECIFIC NUTRITION PLANS FOR PATIENTS WITH DIABETES