The CSIRO Total Wellbeing Diet - Book 2

Introduction

How to lose weight has always been a popular topic of discussion, but that's even more the case since Book One of the CSIRO Total Wellbeing Diet was launched. By the time this second book hits the shelves, over half a million Australians will have a copy of the first book in their possession. This fact has stunned and surprised all of us at CSIRO, but has also given us a sense of the value of our science to the average Australian. We have received countless congratulatory emails telling great success stories, and with many suggestions for future publications. Hopefully the Diet has enthused and inspired many to get healthier and fitter and to make the most of their lives. The feedback from our readers has helped us to understand which issues we needed to clarify, what we needed to describe in more detail and what extra information we needed to include in this book.

The questions and answers we have included here (see pages 29–38) will give you a taste of the wide cross-section of enquiries we had from our readers. Many of you asked for more great recipes, and we don't think you'll be disappointed with the delicious selection we've put together.

Let's face it, all that talk about good nutrition is fine, but most of us just want to cut to the chase and find out how to eat well. The menu plans were extraordinarily popular, as were the shopping lists, which took all the hard work out of preparing healthy meals. This time we've also included some more economical dishes, since some cuts of high-protein foods such as lean red meat and fish can be quite costly. If only we could help you with the cleaning up as well . . .

One of the hardest things about weight-loss is finding inspiration and motivation. That you've bought this book shows that you're on the right track. In it we've tried to provide some short­cuts to help you get started easily and make your weight-loss program a breeze.

The controversy: are the critics right?

Since nutrition scientists are constantly making new discoveries, we need to revise our recommendations for healthy eating from time to time. However, nutrition is an art as well as a science. It's an art because it requires creativity to develop a healthy eating plan for people who differ in their food preferences, beliefs and culture, let alone in their nutritional needs according to their genes and life stage. As we discover more about how our genes and our environment interact, it's becoming increasingly difficult to provide a single set of dietary recommendations that will be suitable for everyone.

What we do know is that there is more than one approach to healthy eating. For example, although this book focuses on a high-protein eating plan, it is also possible to lose weight healthily with a high-carbohydrate or a vegetarian eating pattern. What is important is what works for you.

Our books focus on the CSIRO Total Wellbeing Diet because this eating plan is based on our recent scientific studies, as well as those of researchers overseas. However, CSIRO has also created and published a high-carbohydrate eating plan called the 12345+ Diet. The Dietary Guidelines for Australian Adults, produced by the National Health and Medical Research Council, provide general information on a similarly high-carbohydrate eating style. The Australian Guide to Healthy Eating, produced for the Commonwealth Department of Health and Family Services, is also helpful if you prefer a diet lower in animal protein and higher in carbohydrate. We have found through our research that this style of diet is also effective for losing weight and improving health. If eating more bread, pasta and rice is your preference, then this is the approach for you.

All of these dietary patterns, including the CSIRO Total Wellbeing Diet, share many similarities, such as:

• a high intake of vegetables
• recommendations for high-fibre and less-refined grain foods
• inclusion of low-fat dairy foods, and
• inclusion of lean meat, fish and poultry.

The eating plans differ only in the proportions of foods they recommend, but the CSIRO Total Wellbeing Diet is the only one of these plans that was designed specifically for weight-loss.

Our studies, and those of overseas researchers, have shown that a higher-protein, low-fat diet helps:

• preserve muscle during weight-loss
• enhance loss of fat
• improve vitamin B 12 and iron status, and
• lower triglyceride levels in the blood.

In our studies, those people on a higher-protein diet lost the same amount of weight as those on a higher-carbohydrate diet, since the two diets offered an equal amount of kilojoules and the same amount of fat. However, body composition (that is, the ratio of fat to muscle) showed greater improvement among those people on the higher-protein diet. When the participants in other studies were allowed to eat until they were no longer hungry, those on the higher-protein diet lost more weight than those on the higher-carbohydrate diet, even after more than a year.

The reduction in hunger and the beneficial effect on muscle provided by the higher-protein diet is mostly related to its protein content, while the reduced triglyceride levels and enhanced fat­loss seem to be related to its lower amounts of carbohydrate. The diet is healthy because its protein comes from lean red meat, fish, chicken and low-fat dairy products, all of which provide good nutrition. A high-protein diet in which the protein comes from protein powders and supplements is unlikely to be healthy, unless the supplements are fortified with vitamins and minerals.

Do all protein sources have the same effect on reducing hunger? The answer is: most probably yes. Our studies at CSIRO have shown that animal and vegetable proteins seem to help reduce hunger for up to 4 hours after a meal, so that you don't feel the need for so many snacks.

What has changed since Book One?

The recommended requirements for vitamins and minerals have been revised by the National Health and Medical Research Council (NHMRC). As always, the scientists at CSIRO assisted in reviewing these requirements. The major changes recommended by this review were an increase in calcium and folate intake. The CSIRO Total Wellbeing Diet given in Book One met the original requirements, but the revisions have meant that we now recommend one extra dairy unit each day in the basic plan, to ensure adequate calcium intake. The level of kilojoules is slightly higher, but this will make very little difference to your weight-loss. The increase in recommended folate intake simply means that the minimum daily 2½ cups vegetables are now even more important. We have also made other minor changes to the eating plan, mostly to make it easier to understand and use from day to day.