Diabetes: 6 steps to healthier eating

Healthy eating and diabetes go hand in hand.

People with diabetes have too much glucose (a form of sugar derived from carbohydrates) in their blood.

If blood glucose levels remain high for too long, it can have serious health consequences. Whatever type of diabetes you have, enjoying a healthy diet is the cornerstone to managing it well.

Glucose is found in carbohydrate foods, such as grains, legumes, milk and yoghurt, fruit, sugary foods and starchy vegetables. All of these cause blood glucose levels to rise after eating.

During digestion, glucose reaches the small intestine where it passes into the bloodstream. When glucose reaches body tissues, such as muscle cells, it moves into these cells and is broken down to provide energy. The glucose that isn't needed to fuel the body is stored away in the liver and muscle cells for later use.

However, too much glucose can be harmful. The more carbohydrates you eat, the higher blood glucose level you will have. This is often referred to as a blood sugar spike.

The glucose concentration in your blood is automatically regulated by an essential hormone called insulin. This helps move glucose from the blood into the cells for energy. If you have diabetes, your body is unable to produce enough insulin to move the glucose into the cells. This results in a build-up of glucose in the blood and a raised blood sugar level.

Over time, increased blood glucose levels can cause irreversible problems to the delicate blood vessels and nerves. This can lead to complications such as loss of eyesight, kidney failure, damage to the blood vessels of the heart, and nerve damage in your hands and feet.

The aim of diabetes management is to keep your blood glucose levels within a range that's recommended for you. This lowers the risk of long-term complications, and also reduces the impact of symptoms on your day-to-day life.

These healthier eating habits can help manage diabetes.

Diabetes increases risk of cardiovascular disease,¹ so it's important to do what you can to keep your heart healthy. Too much saturated fat can lead to increased cholesterol levels, which can lead to heart attack and stroke.

Excess fats of any type can also lead to weight gain. Being an unhealthy weight can make your cells less sensitive to insulin, so trying to stay within your healthy weight range is important for your diabetes management.

Eating less fat and switching to healthier monounsaturated and polyunsaturated fats most of the time can help manage your weight and keep your blood glucose levels in your healthy range.

Eat less:

• full-fat dairy foods
• fatty, processed meats such as sausages and salami
• ready-made meals and takeaways which can be high in fat, sugar and salt
• high-fat snacks which may be high in sugar or salt, such as biscuits, cakes, pastries, chocolate and potato chips (these can still be enjoyed sparingly as part of a well-balanced diet).

Replace with:

• low-fat or skim varieties of dairy foods
• lean meat (fat removed) and skinless poultry, tofu, legumes (beans and lentils), and white and oily fish
• home-cooked meals using fresh low-fat and low-salt ingredients, flavoured with herbs, spices, and citrus juices
• avocados, unsalted nuts (such as walnuts, macadamias, almonds and hazelnuts) and seeds such as sunflower and pumpkin.

Omega-3 fats are the essential fatty acids found in fish. They can help keep your heart and blood vessels healthy, reduce blood pressure, and even boost your mood. Some research suggests that omega-3 fatty acids may also help reduce body fat and improve insulin sensitivity.²

It's recommended you eat around 250 to 500mg of omega-3 daily,³ which can be obtained by eating 2 to 3 150g portions of oily fish per week. Omega-3 can also be found in walnuts, canola oil, flaxseeds, chia seeds, soy products and omega-3 enriched eggs.

Carbohydrate-rich foods will cause a rise in your blood glucose levels, but that doesn't mean you have to avoid them altogether. In fact, they play a vital role in our diet as the preferred energy source for our bodies.

The glycaemic index (GI) is a system that measures how quickly a particular carbohydrate-containing food will trigger a rise in blood glucose levels. The lower the GI number, the slower the carbohydrates in the food break down during digestion, and the slower the release of glucose into your bloodstream. This means you're more likely to maintain stable blood glucose levels. Low GI foods may also help you feel full for longer and increase your body's sensitivity to insulin.

Each carbohydrate-containing food is given a GI ranking number between zero and 100:

• Low GI foods are foods with a GI less than 55.
• Intermediate GI foods are foods with a GI between 55 and 70.
• High GI foods are foods with a GI greater than 70.

It's recommended you include one or more low GI foods in every meal or snack. However, low GI foods can still be high in saturated fat and sugar, such as chocolate, so use your judgement.

It's important for people with diabetes to not eat too many high GI foods or too often. Low GI foods will help slow down the absorption of an entire meal, including any higher GI foods, reducing the likelihood of fluctuations in blood glucose levels. So, if you enjoy an occasional treat, have it in small portions as a part of healthy meal of mostly low GI foods.

Eat less:

• white bread and white flour-based foods
• high sugar breakfast cereals
• mashed potato
• white rice
• fruit juices.

Eat more:

• wholegrain breads, rye bread, pumpernickel, fruit loaf, stone ground wholemeal flour, sourdough, wholemeal pita bread, wholemeal chapattis
• high fibre, low sugar breakfast cereals such as those made with wholegrains, nuts and seeds, and bran-based ones
• baked potato with skin, unpeeled boiled Nicola or Carisma potato, or sweet potato
• basmati rice, doongara rice, pasta, noodles (not instant), bulgur (cracked wheat), freekeh, quinoa, and barley
• whole fruits such as apples, pears, grapefruits, peaches, plums, oranges, cherries and firm bananas (though it's still a good idea to take note of the size and the sugar content in these fruits)
• vegetables. Fill half of your plate with veggies and aim to opt for different colours for a wider range of nutrients.

Legumes (also called pulses) contain a wide variety of nutrients and are a good source of protein.

Legumes such as lentils, kidney beans, haricot beans, black-eye peas, black beans, chickpeas, butter beans, and low-salt baked beans contain soluble fibre which dissolves in water to form a thick gel in your intestines. This helps lower blood cholesterol levels and slow down digestion.

They are great added to soups, salads, casseroles and curries.

Legumes do contain low GI carbohydrates, so you still need to monitor how your glucose levels respond, especially if you use insulin or take medicines.

Alcohol is high in kilojoules (energy), while cocktails and pre-mixed drinks can be high in sugar. This means drinking alcohol can raise your blood glucose levels. Drinking a lot of alcohol can also lead to hypoglycaemia (where your blood glucose levels dip dangerously low) if you are using insulin or taking certain diabetes medicines.

It's a good idea to avoid drinking alcohol soon after exercising. During exercise, glucose is absorbed by cells in the exercising muscles, so drinking alcohol afterwards could lower your blood glucose levels further.

Alcohol can also make it more difficult to maintain a healthy weight, as it adds kilojoules to your energy intake and can stimulate your appetite.

Current Australian guidelines recommend that adults should drink no more than 10 standard drinks a week, and no more than four on any one day.⁴

Examples of a standard drink include:

• 375ml of mid-strength beer (3.5% alcohol volume)
• 100ml of red wine (13.5% alcohol)
• 30ml of spirits (40% alcohol).

If you do choose to drink, keep to the recommended limits, avoid sweet wines and beers, and choose sugar-free mixers.

Intermittent fasting and skipping meals may not be suitable if you have diabetes.

Some people can experience a drop in blood glucose levels at night, so it's important to refuel with breakfast in the morning.

Ideally, breakfast should include a mix of low GI carbohydrates, lean protein and fibre. That could mean a boiled egg with wholegrain toast, low-salt baked beans with sourdough toast, muesli or porridge made with traditional oats and fresh or dried fruits, or natural yoghurt with a handful of almonds or walnuts.

Always talk to your doctor before starting an intermittent fasting weight loss program, or any other type of diet change.