Dietary Management of Diabetes

There are two types of diabetes, Type 1 and Type 2. Both are chronic conditions which affect the way your body regulates glucose or blood sugar. Glucose is the fuel your body needs to feed cells. For glucose to enter cells, insulin is produced in the pancreas, circulates in the blood stream, and acts like a key to allow glucose into cells. If a problem occurs, glucose is unable to enter the cells to provide nutrition, and builds up in the blood stream to a level where it becomes toxic.

So what is the difference between Type 1 and Type 2 Diabetes? 

People with Type 2 diabetes have developed insulin resistance. The pancreas still produces insulin but the body is unable to use it effectively. Using the key analogy above, it is as if the lock that allows glucose into the cells has become rusty, and so it is difficulty for glucose to enter cells. This causes the pancreas to produce more insulin to compensate, so insulin levels are high, but the glucose cannot enter cells efficiently. After many years of this process, blood glucose builds to unmanageable levels.

Because people with Type 1 diabetes don’t produce insulin, blood sugar levels can rise very quickly causing damage to the kidneys, eyes, and heart. Especially in those with undiagnosed type 1 diabetes, dangerous diabetic ketoacidosis can develop. People with Type 1 diabetes, therefore, need to be careful when eating foods which contain high levels of sugar such as soft drinks, white bread and pasta. Anyone with the symptoms of new onset Type 1 diabetes (increased thirst, increased urination, weight loss and fatigue) should attend their GP for a finger prick glucose test.

Foods typically recommended for Type 1 diabetes have a low glycemic index. The glycemic index is a measure of how quickly a food impacts blood sugar levels. Foods with a low glycemic index raise blood sugar slowly, while those with a high glycemic index raise blood sugar quickly. It is also recommended that people with Type 1 diabetes have a good understanding of calculating carbohydrate in a meal to help decide on an appropriate dose of insulin.

The timing of meals is also critical for people with Type 1 diabetes. People with Type 1 diabetes usually have to take insulin just before they eat. This ensures the body has enough insulin to absorb the glucose generated. Eating late or skipping a meal may increase a person's risk of developing low blood sugar (hypoglycemia).

The Mediterranean diet is often recommended for people suffering from Type 1 diabetes. This diet typically contains lots of fresh fish, vegetables, fruit and plant fats such as olive oil and nuts. Suggested foods to eat include whole wheat, brown rice, quinoa, oatmeal, fruit, vegetables, beans and pulses, lentils.

Unfortunately, there are a large number of foods which should be avoided by people suffering from Type 1 diabetes including: 

People suffering from Type 2 diabetes continue to produce insulin, so a dramatic onset of symptoms is uncommon. This is a problem, as many people have Type 2 diabetes but do not know, due to the lack of symptoms. Often people don’t know they have Type 2 diabetes until other complications develop such as cardiovascular disease, kidney and nerve damage. 

The good news is that blood sugar levels for Type 2 diabetes can be managed well using a healthy diet. Vegetarian diets are sometimes recommended for Type 2 diabetes. But if you can’t imagine giving up meat the Mediterranean, Paleo and Keto (see below) diets are popular options because they include limited amounts of meat, fish and dairy. 

Whichever diet plan you choose it should contain a mix of fats, proteins and carbohydrates. Any carbohydrates consumed should come primarily from vegetables, while fats and proteins should come from plant-based sources. The diet should consist of complex carbohydrates which are low glycemic foods and provide plenty of other nutrients such as vitamins, fibre and some proteins and fats. These all help to regulate blood sugar levels naturally.

Your diet should consist of foods with a low glycemic index and high in protein. This means a diet rich in fruit, vegetables, beans, lentils and oatmeal. You should avoid foods containing simple carbohydrates and processed foods which contain high levels of sugar or simple carbohydrate such as pasta, flour, white bread, white rice, biscuits, pastries and soft drinks (diet and regular).

Gestational diabetes develops during pregnancy and is not a chronic condition unlike other forms of diabetes. It does mean you have a higher chance of developing Type 2 diabetes later in life. The condition is usually diagnosed in the last 12 weeks of pregnancy through the routine Glucose Tolerance Test at 26-28 weeks, and resolves after birth. If the condition continues after birth it’s usually because the patient had diabetes before falling pregnant. It is essential that an expecting mum closely adheres to a gestational diabetes diet.

Gestational diabetes is caused by hormonal changes in the body during pregnancy. This makes it more difficult for cells to use insulin properly, effectively creating a condition similar to type 2 diabetes. This means that mangement with exercise and a healthy diet is the mainstay of treatment, although due to the effect of high blood sugar on pregnancy and a growing baby, insulin is often required to keep blood glucose at an acceptable level.

Not all pregnant women will develop gestational diabetes, it affects around 16 in 100 pregnancies. Women who are overweight or clinically obese are much more likely to develop the condition. Your healthcare professional will routinely test for the condition at around twelve weeks prior to your due date, but if you feel you are in a high-risk group take advice as soon as possible. 

You should avoid eating foods high in sugar and simple carbohydrates including processed foods and sugary drinks such as: 

If you need to snack during pregnancy you should avoid biscuits, chips and chocolate. Try and stick to healthy alternatives such as unflavoured greek yoghurt (Jalna brand is a good choice), fruit, unsalted nuts and vegetables.

Over recent years, the Ketogenic diet, or Keto diet for Diabetes, has become popular for people suffering from Type 2 diabetes. The diet is high in fat and low in carbs, which changes the way your body stores and uses energy. This eases the symptoms of diabetes by reducing demand on the pancreas for insulin release, and lowering blood glucose levels. 

Several studies have shown that the Keto diet encourages the body to use fat for energy instead of glucose or carbohydrates. Participants in the studies saw improvements in glycemic control and reduced dependency for insulin. 

A Keto diet doesn’t mean you can go out and load up on saturated fats though. The diet is made up of healthy monounsaturated and polyunsaturated fats, the kind which is found in vegetables and dairy products.

You should avoid foods which contain high levels of saturated fats or sugar including: 

Changing the body’s primary source of energy from carbohydrate to fat and protein is potentially dangerous for those requiring insulin to manage their diabetes. A ketogenic diet should never be commenced in those using insulin or oral medication for diabetes without medical supervision. Risks include severe low blood sugar (hypoglycaemia) and diabetic ketoacidosis.  

You are therefore advised to consult a healthcare professional before trying the Keto diet. While on the diet, you should also monitor your blood sugar levels throughout the day to make sure they remain within target levels. A home testing kit is available. If you experience symptoms of DKA which include a dry mouth, frequent urination and nausea, you should contact a doctor immediately.

Growlife Medical provides comprehensive community-based Diabetes advice. 

We are also Brisbane's leader in Telehealth Consults, Growlife Medical now provides easy and secure Telehealth Consults with your doctor. You can easily book online or over the phone, for a video or phone consult with your GP. All Growlife Medical Doctors in all or our general practice locations are available for Telehealth consults.