Introduction

Diabetes mellitus (DM) is a complex chronic progressive illness. Diabetes is rapidly increasing in the United States. According to the CDC’s (Centers for Disease Control) National Diabetes Statistics Report for 2020, diabetes cases have risen to an estimated 34.2 million ( Diabetes Research Institute, 2020). Ongoing diabetes self-management education involving diet and exercise are critical to disease management.

The metabolic disturbances characteristic of DM occur due to a lack of insulin or resistance to the effects of insulin at target organs. There are four main classes of DM: prediabetes, type 1, type 2, and gestational diabetes.  

Prediabetes is a condition in which blood glucose is elevated above normal but not high enough to be classified as diabetes. An estimated 88 million adults aged 18 and older had prediabetes in 2018. Without intervention, prediabetes can progress to diabetes in as few as ten years. Prediabetes can cause damage to the cardiovascular system long before DM is diagnosed. However, studies have shown that progression from prediabetes to diabetes is not inevitable.

Behavioral and psychological orientations are at the heart of achieving and maintaining treatment goals. According to the ADA 2019 consensus, “all patients with prediabetes should be referred to a behavioral lifestyle intervention program.

Diabetes is primarily a self-managed disease. Every day patients must make many decisions impacting the management of their prediabetes or diabetes. The American Diabetes Association believes that a one size fits all treatment of diabetes and prediabetes is unrealistic given the broad spectrum of people affected, their cultural backgrounds, personal preferences, co-occurring conditions (often referred to as comorbidities), and socioeconomic settings in which they live (Evert 2020).   Effective diabetes management requires shared decision-making. Nutritional therapy, physical activity, smoking cessation, and often counseling is necessary to effectively manage diabetes (Evert, 2019).

The National Academy of Medicine (formerly the Institute of Medicine) broadly defines nutrition therapy as the treatment of a disease or condition through the modification of nutrient or whole-food intake.
Medical nutrition therapy (MNT) is an evidence-based approach to care that includes:  assessment, nutrition diagnosis, interventions (e.g., education and counseling), and monitoring with ongoing follow-up to support long-term lifestyle changes, evaluate outcomes, and modify interventions as needed (Evert, 2019).

The goals of diabetes management are to help the patient safely attain and maintain nutrition and lifestyle changes that reduce the risk of diabetes complications.

Type I DM  is the result of the autoimmune destruction of pancreatic beta cells. Type I accounts for 5-10% of DM. The onset of type 1 usually occurs in childhood or young adulthood. Risk factors for Type 1 DM include genetic propensity and environmental exposures that trigger an autoimmune response. People with type 1 diabetes require exogenous insulin to manage their disease. Without exogenous insulin, skeletal muscle and fat cannot lower blood glucose by absorbing and storing excess glucose. Without insulin, the pancreatic hormone glucagon is free to mobilize hepatic glycogen, skeletal muscle protein, and fatty acids in a futile attempt to provide the body with fuel. The result is hyperglycemia and its associated pathologies. The treatment of Type 1 DM in adults focuses on: correction of acute health conditions, MNT, self-care education, self-monitoring of blood glucose (SMBG)), insulin therapy, and the management of late complications.

Latent Autoimmune Diabetes in Adults (LADA) diabetes is rare and known as “late-onset” diabetes. LADA is sometimes called type 1.5 diabetes. LADA progresses slowly and is often a misdiagnosis of Type 2 diabetes. Many LADA patients are treated with oral medications, but eventually, the pancreas will stop producing insulin, as in type 1 diabetes, and insulin injections are required. This can take anywhere from a few months after diagnosis to several years. (https://beyondtype1.org/what-is-lada-diabetes/)

Type 2 DM accounts for about 90% to 95% of all diagnosed cases of DM. Type 2 is associated with older age, obesity, family history of diabetes, history of gestational diabetes, impaired glucose metabolism, physical inactivity, and race/ethnicity. Type 2 DM used to be known as adult-onset diabetes, but since the late 1990's it is increasingly being diagnosed in children and adolescents. Type 2 DM patients produce insulin, but the quantity may be insufficient, or the target organs may not respond. Type 2 is often a progressive disease, but nutrition and lifestyle changes can slow or halt the disease process. Treatment of type 2 DM focuses on weight loss, MNT, physical exercise, continuing medical care, and self-management.

Gestational diabetes mellitus (GDM) is a growing health risk to both the mother and child. A large study in Los Angeles County, California, found that gestational diabetes prevalence increased threefold from 14.5/1000 singleton deliveries in 1991 to 47.9/1000 singleton deliveries in 2003. GDM is defined as any glucose intolerance that manifests during a pregnancy. There are two forms of GDM. Pregnancy-related endocrine factors induce the first. The second is chronic maternal insulin resistance that is unmasked by pregnancy. Management of GDM includes individualized medical nutrition therapy, daily self-monitoring blood glucose, planned physical activity, and insulin when needed.

It is vital to involve the diabetic person’s family and significant others in the diabetes care plan. These individuals purchase and prepare food, provide encouragement and support for the person with diabetes. Diabetic individuals often find that making nutritional changes to be one of the most significant challenges they face in disease management. A successful treatment plan will incorporate nutrition and lifestyle changes the patient is willing and able to make.

Cultural and ethnic considerations are also important. All persons with diabetes, whatever their age, type of diabetes, or disease severity, must be aware of the vital importance of dietary management. In American culture, food is often associated with love and rewards. Handing a newly diagnosed diabetic person, a pre-printed diet without carefully personalizing each unique individual's plan will not work for most people with diabetes.