Proteins: the foods that fill you up

Nobody wants to feel hungry or unsatisfied when they are trying to lose weight. Choosing foods that provide eating satisfaction without a lot of kilojoules is a successful strategy for many dieters. Fat was once thought to be the fill-you-up nutrient, but a growing body of research shows that protein may have the edge.

Protein offers more satisfaction for fewer kilojoules

Eating foods with a high satiety value helps extend the time between meals and the amount of food needed to stop hunger. Both of these factors can reduce the number of kilojoules consumed in a day, resulting in weight loss. In a new study conducted at the University of Washington in Seattle and the University of Oregon in Portland, researchers showed that people eating meals with varying amounts of protein and fat fared better with weight loss when their meals contained more protein. The higher-protein meals produced greater satiety and a desire to eat fewer kilojoules, leading to a greater loss of weight and body fat.

Playing the percentages

The diets used in the study were not extreme, fitting into the recommended ranges for both protein and fat. The higher fat diet had 15% of kilojoules coming from protein and the higher protein diet had twice that amount. While satiety levels were greater on the higher protein regimen, the reason why is unclear because the study also found no impact on either ghrelin or leptin, two hormones known to affect hunger and appetite.

If hunger and a lack of eating satisfaction are impeding your weight-loss efforts, you may want to try the approach used in this study and look for ways to cut fat kilojoules and increase protein. Low-fat, high-protein foods include lean cuts of meat (look for words like 'trim' and 'HeartSmart' on the label), skinless poultry, fish, egg whites, low- or nonfat dairy products, and beans and legumes.

How does protein work?

In the body, protein foods are digested and broken down into individual amino acids. The body then uses these amino acids to synthesise new proteins for growth and body repair. Muscles, skin and hair are just a few of the body parts that are made up of proteins. Amino acids are also used in metabolic processes in the body.

There are two broad classes of amino acid: those that can be made by the human body (non-essential amino acids) and those that can only be supplied by food (essential amino acids). It is for this reason that protein is so important in a healthy diet.

How much protein should you eat?

The Weight Watchers Good Health Guidelines recommends one to two serves a day. This includes lean meats and skinless poultry (both a great source of vitamins and minerals, such as iron, selenium, zinc and B vitamins), fish, seafood, eggs, soy products, beans, lentils, nuts and seeds.

Australia National Health and Medical Research Council (NHMRC) recommends we eat at least two serves of fish a week (a serve is about 140g), one of which should be oily such as salmon, mackerel, or sardines. Fish is rich in protein and minerals, and oily fish is rich in Omega-3 fatty acids, important for good health.

What if I'm vegetarian?

Animal sources tend to contain all of the essential amino acids, whereas most plant sources often lack one or more. For this reason, vegetarians and vegans need to include protein from a variety of plant sources such as legumes, nuts, cereals, soy products, eggs and dairy (if eaten) to ensure the right balance of amino acids are consumed.

Protein-rich ingredients

  • Canned tuna:  Easy and inexpensive, canned tuna is a fantastic way to incorporte protein into your lunches.
  • Chicken breast:  Chicken contains a similar amount of protein to red meats, and is a valuable source of iron and zinc. To maximise the nutritional benefits, always choose skinless.
  •  Eggs:  Eggs represent a valuable, occasional protein alternative to meat.
  • Fish:  The oily fish are a very rich source of omega-3 fatty acids, which have been shown to provide specific health benefits, notably in relation to brain development and function and cardiovascular health.
  • Lean meat:  Red meats are a valuable source of dietary protein and the best sources of bioavailable iron in the Australian diet. They also provide substantial amounts of zinc and vitamin B12.

Read more about healthy weight loss:

This content was written by Karen Miller-Kovach and Weight Watchers as part of Kidspot's Positively Life Changing initiative.

Last revised: Monday, 10 January 2011


blog comments powered by Disqus