There is so much information about what to eat and what not to eat that it can get quite confusing. Here you can find fact-based answers to some common questions about healthy eating.
Should carbohydrates be part of a healthy diet?
Yes, but some carbohydrates are better for you than others.
Carbohydrates are important and form part of a healthy diet. High quality, carbohydrate-rich foods include wholegrain foods such as wholegrain bread, legumes, vegetables and fruit. These foods provide energy, fibre, vitamins and minerals and phytonutrients (beneficial chemicals found in plants).
Poor quality carbohydrates provide energy but few other nutrients. These foods include sugar and sugar-rich foods and drinks, and refined grains like those used in white breads. Many foods combine sugar, refined grains, fat and salt, such as some highly processed breakfast cereals, cakes, biscuits, crackers and many snack foods. These foods should be eaten occasionally.
Are foods high in saturated fat, like butter, healthy?
No, the evidence still points to the benefits of having a low saturated-fat intake.
Foods high in saturated fat include butter, cream, cheese and the fat from meat, as well as coconut oil and palm oil. Research over many years has shown a link between saturated fat, blood cholesterol levels and heart disease.
It’s recommended you replace saturated fats with polyunsaturated fats to reduce the risk of heart disease and stroke. That means using unsaturated fats such as plant-based oils and spreads instead of butter, if needed for cooking and spreading.
Should people avoid fruit because of its sugar content?
No, fruit is an important part of any varied, healthy diet.
However, it’s recommended you decrease the amount of ‘free sugars’ you eat. These are sugars added to foods, as well as sugars that are naturally present in fruit juice, syrups and honey. This doesn’t apply to the sugar found naturally in foods such as whole fruit and dairy products.
As well as sugar, whole fruit provide a range of nutrients including dietary fibre and phytonutrients.
Are aspartame and other ‘intense (artificial) sweeteners’ safe?
Intense (artificial) sweeteners approved for use in New Zealand are considered safe.
Stevia, or steviol glycosides, is one of the intense sweeteners approved for use in New Zealand. It’s extracted from the leaves of the Stevia rebaudiana Bertoni plant, from the sunflower family. Stevia has no energy (kilojoules) and doesn’t increase blood glucose levels.
Foods and drinks containing intense sweeteners should be consumed in moderation. They can play a useful role within a healthy diet, but you should choose fewer sweet foods and drinks to get used to the taste of less sweetness.
Is a low-carbohydrate, high-fat diet the best way to lose weight?
No, evidence shows it’s the total energy (kilojoules) in a diet that’s important, not what type of foods that energy comes from.
While you can lose weight with some low-carb, high-fat diets, this happens with other energy-controlled eating plans as well. There is also no evidence of the long-term benefits or safety of such diets.
Is the paleo diet healthy?
While it has some healthy features, overall the paleo diet is not a healthy eating plan.
The paleo diet is based on the diet of early hunter-gatherer humans from the Palaeolithic period (around 2.5 million to 10,000 years BC). It consists of vegetables, some fruit, nuts, naturally occurring fats and oils, meat and seafood. It excludes dairy products, grains, legumes, processed oils, sugar, salt, alcohol and coffee.
It's difficult to copy a true paleo diet as very little is known about the diet of early humans. Many of the plant and animal foods around during the Palaeolithic period don’t exist anymore. Also, the diet excludes entire food groups that are important such as grains, legumes and dairy products.
Are intermittent fasting diets like the ‘5-2 diet’ good for weight loss?
Intermittent fasting diets might work for some people, but they can have negative side effects.
The 5-2 diet, where a person has 5 days of normal eating and 2 days of a much lower energy intake is not recommended for people with insulin dependent diabetes.
The little research available on intermittent fasting diets has shown people can lose weight following this eating plan. At present though, no studies have shown how sustainable this eating pattern is or how it impacts on long-term weight or health outcomes.
Possible immediate side effects from the fasting days are extreme hunger, low energy levels, light-headedness and poor mental functioning. The quality of the diet on normal days will also impact on health outcomes in the long term.
Do you need to take dietary supplements?
No, most people don’t need to take dietary supplements.
Getting nutrients from foods rather than supplements is considered best. Foods, particularly plant foods, provide a range of health-promoting nutrients beyond vitamins and minerals. Some of these are known, such as flavonoids and some antioxidants, while others remain unidentified.
In some situations supplements are needed, eg, if you’re pregnant, breastfeeding, or iron or vitamin D deficient. If you’re in any of these situations or need more information about supplements, please talk to your doctor.
- Eating and activity guidelines for New Zealand adults: Topical questions and answers Ministry of Health, NZ, 2015