Are you interested in protein? Do you actually know what proteins are and why you need them in your diet? Do you know what foods contain protein?  Do you know what the current recommendations are for protein? Are there any special protein recommendations for people with diabetes? If these are some of the questions you have on protein this blog is for you!  Presented are eight of the most popular questions and their answers dealing with protein.

1. What are Proteins?
In chemistry, when 2 or more atoms join together, they make a molecule.(1) Proteins are large molecules made out of smaller molecules called amino acids. There are 20 amino acids that make up proteins. The atoms that amino acids contain include hydrogen, oxygen, carbon, and nitrogen.(2)  Two particular amino acids, cysteine and methionine, also contain sulfur that are incorporated into proteins.(3)  It is interesting to note that plants can synthesize all of the amino acids they need using atoms as building blocks. Humans and other animals need all 20 amino acids to survive but can only make 10 out of the 20 that are needed.  We obtain the other 10 amino acids by eating plants that made them, or animals that have consumed these plants somewhere along the food chain.(4)

2. What are the functions of protein in the body?
Proteins are essential to our survival. Some of the functions of proteins include the following:
1.    They provide the structure and support to our cells. (5)
2.    They are involved in cell division and gene expression. (6)
3.     Enzymes are proteins which helps speed up chemical reactions in our body.(6)
4.    Antibodies are proteins which help fight infection.(6)
5.    Our muscle fibers are made of protein. (7)
6.    Our hormones, including insulin and glucagon, are proteins. (6,8)
7.    Proteins control the signaling in our brains. (9)
10. Proteins can also provide energy. The caloric value of protein is 4 calories per gram. (10)

3. What foods provide protein?
Meat and dairy products provide animal sources of protein. Plant based protein can be found in beans, peas, lentils and vegetables. Starchy foods also contain variable amounts of protein. We have nutritional information on different foods and the amount of carbohydrate, protein and fat they contain.

For additional information,

4. How much protein do I need?
According to the National Academy of Sciences. Institute of Medicine. Food and Nutrition Board:
The Recommended Dietary Allowance (RDA) for most healthy adult men and women is 0.8 grams of protein per kilogram of body weight per day. A kilogram is approximately 2.2 pounds. Using pre-pregnancy weight, the RDA for pregnant and lactating women is 1.1 grams of protein per kilogram of body weight per day.(11) The average amount of protein ingested by people with diabetes is 16-18 percent of calories ingested.(12)

5. Are there any special protein recommendations for people with diabetes?
 In October of 2013, current Nutrition Therapy Recommendations for the Management of Adults with Diabetes was published by the American Diabetes Association's journal Diabetes Care. (12) In addition the Standards for Medical Care for Diabetes was released in January of 2013.(13)

The following protein recommendations were made in these two reports:
• People with diabetes should receive individualized medical nutrition therapy (MNT) when needed to achieve treatment goals.  The preferred provider would be a registered dietitian who is familiar with the components of diabetes MNT. If outside of the United States, a person with similar education and experience should be used.(12)
• Evidence suggests that there is not an ideal percentage of calories from carbohydrate, protein, and fat for all people with diabetes; therefore, macronutrient distribution should be based on individualized assessment of current eating patterns, preferences, and metabolic goals.(12) (Macronutrients are nutrients that are needed in large amounts. They include carbohydrates, proteins and fats.)(14)  In addition, individualization of the macronutrient composition will depend on the metabolic status of the patient (e.g., lipid profile, renal function).(13) This means the standards are for the dietitian to look over laboratory values, medical information, patient food preferences, dietary needs and patient goals before writing a food plan.
• For people with diabetes and no evidence of diabetic kidney disease, evidence is inconclusive to recommend an ideal amount of protein intake for optimizing glycemic control or improving one or more cardiovascular disease (CVD) risk measures; therefore, goals should be individualized.(12)
• For people with diabetes and diabetic kidney disease (either micro- or macroalbuminuria), reducing the amount of dietary protein below usual intake is not recommended because it does not alter glycemic measures, cardiovascular risk measures, or the course of  Glomerular filtration rate (GFR) decline.(12)
•The standards of medical care give more specific recommendations. They are: Reduction of protein intake to 0.8–1.0 grams per kilogram body weight per day in individuals with diabetes and the earlier stages of chronic kidney disease (CKD) and to 0.8 grams per kilogram body weight per day in the later stages of CKD may improve measures of renal function (urine albumin excretion rate, GFR) and is recommended.(13)
•In individuals with type 2 diabetes, ingested protein appears to increase insulin response without increasing plasma glucose concentrations. Therefore, carbohydrate sources high in protein should not be used to treat or prevent hypoglycemia. (12)

6. Do I need to eat meat to get enough protein?
 According to the Academy of Nutrition and Dietetics, people can get enough protein by eating a variety of plant proteins throughout the day. By doing this, one can directly get all the essential amino acids needed by the body. (15)

7. Are there any special protein concerns for women planning for a pregnancy and the risk of gestational diabetes?
There was an extremely interesting perspective cohort study on this question. Results showed that when women ate a higher amount of animal protein (especially red meat), it was associated with a greater risk of gestational diabetes.  Women that ate a higher intake of vegetable protein instead of the animal protein plus healthy protein sources instead of red meat had a lower associated risk of gestational diabetes mellitus.(16)
8. Are there any recommendations for the general population concerning protein consumption (including people with diabetes and without diabetes) beyond those discussed above?
The American Institute for Cancer Research has two recommendations pertaining to protein that may help reduce the risk of colon cancer in people with and without diabetes. They are:
•    Limit red meat to no more than 18 ounces per week
•    Avoid highly processed meats. Examples of processed meats are hot dogs, bacon, sausage and deli meats.(17)
As you can see, protein is a very important part of our diets. For people with diabetes it is highly recommended to have a dietitian on your medical team help you work towards your medical nutrition goals. She/he will also help you determine the protein you need using foods you enjoy best.

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