Home / Resources / Clinical Gems / Joslin’s Diabetes Deskbook, Updated 2nd Ed., Excerpt #20: Food Labels

Joslin’s Diabetes Deskbook, Updated 2nd Ed., Excerpt #20: Food Labels

Nov 24, 2012

Amy P. Campbell, MS, RD, CDE, and Richard S. Beaser, M.D.


 The weeks excerpt answers the following questions:


  • How to teach your patients to read food labels
  • What "dietetic" foods actually are
  • How much alcohol will affect blood sugars
  • How to use insulin if fasting
  •  When and how to use food records

Food Labels

People have become more conscious of what they eat and the ingredients of the foods that they purchase. In 1994, the US government mandated that specific nutritional information be provided on food labels, making it easier for everyone, including people with diabetes, to determine more precisely what they are consuming. Ingredients are listed, as well as calories per serving and amounts of protein, carbohydrate, and fat.

There are still many pitfalls in understanding labels. Some are difficult to read and hard to understand. Words do not always mean what they say, particularly with regard to the so-called "dietetic" foods.

Patients should be advised to pay particular attention to the serving size, as the other nutritional measures, such as calories, fat and carbohydrate, are based on this parameter. The serving size may or may not relate to the serving size on exchange lists, but can be used for comparison. When advising patients about label reading, ask them what serving size they would usually have. Remind them that if they usually eat one cup and the portion on the label is for 1/2 cup, they are getting twice as many nutrients and calories.

An example of a healthy food product is defined as the following and can be used in comparing items:

  • saturated fat <1 gm/serving
  • low-fat < 3 gms/serving
  • fiber >3 gms/serving
  • sodium
    • snack item: <400 mg/serving
    • entree <800 mg/serving
As of January 1, 2006, the FDA requires all food manufacturers to list the trans-fat content on the Nutrition Facts label. Trans-fat, just like saturated fat, can raise LDL cholesterol levels, increasing the risk for heart disease. At this time, there is no Daily Value for trans-fat, but the overall goal is to educate patients to choose foods with as little trans-fat as possible.

"Dietetic" Foods

Many people mistake "dietetic" for "diabetic." Another common error is to assume that all "dietetic" and "sugar-free" foods are low in calories or have no carbohydrate. This is not true, and can be misleading to many patients.

In the past, patients were advised to strictly avoid sucrose, but this is not felt to be such a concern today. The total carbohydrate and caloric contents are important, however. Thus, patients need to be informed consumers and read past the packaging designations and consult the actual nutrition labeling. Some "dietetic" foods may be useful for people with diabetes. These include sugar-free soft drinks, sugar-free gelatin, artificial sweeteners, dietetic jellies and syrups, and reduced-calorie salad dressings. The most important point is to read the label. Even if the product is lower in calories than the "real" product, such foods still may contain more calories than the consumer bargained for. Also, patients should look out for the nutritive sweeteners (sucrose, fructose, and sorbitol) that can still affect blood glucose levels.

The labeling laws allow manufacturers to declare an item "sugar-free" in bright, bold print. The "sugar" that they are referring to is sucrose, and often the print is less bold when they state that they have replaced the sucrose with another carbohydrate (such as fructose, sorbitol, or others). These may have as many calories and carbohydrates, and may cause an elevation of blood glucose level equal to the sucrose they replaced.

The "dietetic" designation only indicates that the product has fewer calories than the standard version. For example, "diet candy" may have only 80 calories per piece, where the "regular" version has 150. Also, beware of what might have been used to replace the missing calories. For example, in the candy in question, the fat content might have been increased so as to maintain the expected consistency. Thus, the "healthier" soundingproduct might not be as healthy as the regular counterpart.


Alcohol may be used in moderation by patients who have good glucose control and for whom there is no other contraindication. Alcohol blocks hepatic glucose production, which can functionally increase the clinical efficacy of insulin and make recovery from hypoglycemia more difficult. Also, the effects of alcohol consumption can have detrimental effects on a patient’s ability to follow self-care procedures or to recognize early hypoglycemic symptoms so as to prevent more severe consequences.

Keep in mind also that alcohol contains calories, so that even without other specific reasons to restrict drinking, those patients following a calorie-restricted meal plan must include the caloric content of such beverages in the daily intake calculation. In addition, calories from alcohol lack nutritional benefit, and should not be substituted for more important components of the nutrition prescription. Often, reduction of the calories in alcohol consumption can be a successful component of a weight-loss strategy.

Nevertheless, in recent years, the evolution of more responsible attitudes toward alcohol consumption and the availability of products such as light and alcohol-free beers have made the social aspects of moderate drinking more compatible with adherence to nutritional plans for people with diabetes. When incorporating alcohol into a nutrition program, a compensatory reduction in fat intake should occur based on the quantity of alcohol consumed at 7 kcal/gram. The carbohydrate content of sweetened drinks must also be taken into consideration.

Alcohol recommendations for adults with diabetes are similar to those for the general public: men should limit alcoholic drinks to two or less per day, and women one or less per day. One "drink" contains about 15 grams of alcohol and is defined as:

  • 12 oz. of beer (preferably light)
  • 5 oz. wine
  • 1 1/2 oz. distilled spirits (scotch, whiskey, rum, vodka) 

People with diabetes who take insulin or diabetes pills that can lower blood glucose levels should be instructed to drink alcohol with food to reduce the risk of hypoglycemia. No food should be omitted in exchange for an alcoholic beverage.

Certain people should not drink alcohol, including pregnant and lactating women, and those people with medical problems such as pancreatitis, advanced neuropathy, and alcohol abuse. Patients with extremely elevated triglyceride levels should be encouraged to avoid alcohol. Excessive amounts of alcohol may increase blood pressure and may worsen diabetic retinopathy. Finally, patients who take metformin should avoid drinking large amounts of alcohol due to the increased risk of lactic acidosis.

Vegetarian Diets 

A properly designed vegetarian meal plan can be very healthy. Vegetarians often have a lower morbidity and mortality from macrovascular diseases (which are worsened by dietary fats found in animal meat) than do nonvegetarians. In addition, a vegetarian eating plan may lower blood pressure and lower the risk of some types of cancer. Vegetarian diets are inherently higher in carbohydrate, but planned carefully, they can be well tolerated. It is important that patients and patients’ families be well educated when adopting this type of nutrition plan, especially if the diet is for a child with diabetes, as deficiencies may develop, particularly of iron, calcium and/or vitamin B12.

Legumes (dried beans and peas) have a very low glycemic index and their high fiber content can help lower cholesterol levels. People who follow a strict vegetarian ("vegan") diet (eliminating all animal protein including dairy and eggs) must ensure that they derive their protein sources from legumes and grains in order to maintain an adequate intake of protein. Patients who are interested in following a vegetarian meal plan should be referred to a registered dietitian.


Fasting is not recommended for people with diabetes, particularly those treated with insulin. For those with type 2 diabetes, consuming food is important to stimulate endogenous insulin, and thus is important in metabolic homeostasis. Fasting for the purpose of losing weight can be dangerous for anyone and should not be undertaken except under strict supervision by a physician.

For some, there are religious reasons to fast. Some people fast for periods of about a day, such as for the Jewish holiday of Yom Kippur. Over the years, rabbis have been confronted with the question of how people with diabetes should handle this situation. Many have suggested that an individual’s health takes precedence over religious observance and have therefore condoned the decision not to fast. Some live the "spirit" if not the letter of the law by consuming a drink of sugar-containing liquid (juice or soda) every hour or two, to equal 1 ounce for every hour of fasting. Some choose small amounts of food. In response to this approach, some rabbis have commented that while a full meal would be a big sin, many small snacks would be just tiny sins and in total would not be very much of a sin at all.

The fast of Ramadan, observed by Muslims, represents a one-month period in which only two meals are eaten, an early breakfast and a later dinner with no lunch. The duration of fasting extends for 8-16 hours between sunrise and sunset and depends on the season of the year. Insulin sensitizing medications do not cause hypoglycemia and are usually safe in comparison to insulin-stimulating medications, which should be limited to use with the evening meal if needed. Insulin regimens usually need some adjustment. Avoidance of NPH insulin (due to peaking during fasting), and use of longer-acting insulin and rapid-acting insulin are preferable. Using SMBG may help in appropriate adjustments of diabetes treatment to compensate for this time change. As for diet, it is advisable to delay the first meal as long as possible toward sunrise. It is also advisable that this meal contain a higher percentage of calories from protein and carbohydrate that are high in fiber content to last for a longer period during the fast. The morning dose of rapid or short-acting insulin must be lowered by 20–30%. The second meal should be a balanced meal with a modest amount of carbohydrate to avoid a sudden rise in blood glucose levels. Many people prefer to eat a smaller snack, like soup or dates, followed within a few hours by a larger meal. In such instances, insulin should be injected with the larger meal to avoid insulin overlap. Dates are very high in carbohydrates and should be limited to 1–2 pieces for breaking the fast. Sweets that are high in sugar should be avoided and sweeteners should be used when applicable.

Food Records 

People with diabetes are often asked to keep records of their food and/or carbohydrate intake, as well as activity level and blood glucose results. A completed food record is an invaluable tool to determine if the current diabetes treatment plan is successful or not. Encourage patients to keep at least a three-day food record prior to seeing a dietitian for the first time. Thereafter, a dietitian may ask the patient to continue to keep food records, especially if the patient is experiencing fluctuating blood glucose levels, is trying to lose weight, or is in the process of evaluating an insulin-to-carbohydrate ratio, for example. A note of interest from the National Weight Control Registry: participants who periodically kept food and activity records were more likely to be "successful losers."



Next Joslin Excerpt: Food Labels

Copyright © 2010 by Joslin Diabetes Center. All rights reserved. Reprinted with permission. Neither this book nor any part thereof may be reproduced or distributed in any form or by any means without permission in writing from Joslin. Note: Joslin does not endorse products or services.

For Excerpt #1 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here.

For Excerpt #2 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here.

For Excerpt #3 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here.

For Excerpt #4 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #5 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #6 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #7 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #8 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #9 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #10 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #11 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #12 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #13 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #14 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here. 

For Excerpt #15 from the Joslin Diabetes Deskbook, 2nd Ed, in this series, just click here.  

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Please Note: Reasonable measures have been taken to ensure the accuracy of the information presented herein. However, drug information may change at any time and without notice and all readers are cautioned to consult the manufacturer’s packaging inserts before prescribing medication. Joslin Diabetes Center cannot ensure the safety or efficacy of any product described in this book.

Professionals must use their own professional medical judgment, training and experience and should not rely solely on the information provided in this book to make recommendations to patients with regard to nutrition or exercise or to prescribe medications.

This book is not intended to encourage the treatment of illness, disease or any other medical problem by the layperson. Any application of the recommendations set forth in the following pages is at the reader’s discretion and sole risk. Laypersons are strongly advised to consult a physician or other healthcare professional before altering or undertaking any exercise or nutritional program or before taking any medication referred to in this book.