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Can’t keep weight off? Blame your hunger hormones

Losing weight is hard, but holding onto hard fought gains can be even harder. Weight regain is faced by almost all successful weight losers, resulting in the need to turn to yet another variation of the dieting, exercising and self-denial merry-go-round ride.

Weight regain is well described in the medical literature, but the reasons for it are not entirely clear. Plateauing of weight loss and a subsequent drop in motivation to keep up the changes in diet and exercise changes certainly play an important role.

Australian researchers have added a new piece to the puzzle of weight regain, by studying how the hormones that drive us to eat and make us feel full can change after a period of weight loss.

Antioxidant supplements no help in preventing heart disease

A comprehensive scientific review has concluded that a range of popular vitamin and antioxidant supplements fail badly in showing any evidence that they can help cut the risk of heart disease.

Cardiovascular disease (CVD) is a major cause of death in developed countries and is largely influenced by food and lifestyle choices. CVD is an umbrella term which includes heart attacks, heart disease, stroke and claudication (tiredness in the legs) of the peripheral blood vessels. Taking antioxidant supplements has been promoted for many years as being a valuable aid in helping someone prevent CVD, but just how effective are these supplements?

Antioxidants such as vitamins C, E and beta-carotene are part of the body’s defence system and their main role is to mop up damaging free radicals. Free radicals are a normal by-product of body metabolism, but high levels can be found in people who are smokers or have a poor diet.

Green tea: hype over substance for weight loss

Green tea is an increasingly popular weight loss supplement. A comprehensive review of the clinical evidence though has found that a person’s bank balance is probably the only thing that will get lighter by buying these supplements or consuming foods and drinks that have it added to them.

Green tea is a popular beverage with a long history of human consumption. Improvements in heart health, lower cancer risk and sharper mental function have all been linked to drinking green tea.

The 'worried well': supplementing an already healthy diet

New research has found that people who take mineral supplements actually consume more minerals from their normal diet than non-supplement users. The notion of the 'worried well' is certainly alive and kicking

Vitamin and mineral supplements are big business. Reported figures in Australia suggest that 27% of women and 15% of men take some form of supplement with vitamin C, B complex, multivitamins, vitamin E and calcium all being popular choices.

Contrary to the rationale for needing supplements in the first place, people who take supplements are more likely to be healthier than people who don’t take supplements. Supplement users also tend to be leaner, smoke less, exercise more, and eat more fruit and vegetables.

New dietary guidelines for Australians released

Today marks the release of the revised Australian Dietary Guidelines. So what has changed since the last update in 2003? Very little in the way of the main recommendations, but the evidence base for the guidelines has grown stronger.

Soup satisfies a hungry appetite

A simple bowl of soup has been found to be an effective way to curb appetite and promote feelings of fullness.

True hunger is a rare experience for most people in the developed world. What people typically experience are feelings of desire for particular foods or a need to feel ‘full’

Satiety is the term scientists use to mean the feelings of fullness we experience after a large meal. What drives satiety is a complex mix of psychological and physiological factors including physical stretching of the stomach and small intestine from food and a cascade of release of hormones that feed back into the brain to tell us we are full.

Dietary supplements offer little benefit for most people

A comprehensive review of clinical trials involving a wide range of popular dietary supplements has found that with the exception of vitamin D and omega-3 fatty acids, there is little evidence to support their use in Western countries by the general population.

Dietary supplements are big business, with around half of the Australian population using at least one type per year; most commonly a multivitamin and mineral pill. Many people take supplements as a form of dietary insurance in case they are not meeting their nutrient needs from foods alone. Others take them as a form of health insurance – to protect against certain diseases. Some just take them out of habit.

Supplements do have a role to play in some situations. People with a diagnosed deficiency, those with malabsorption conditions, women planning pregnancy, and people with very poor diets all can benefit from specific nutrient supplementation.

What drives us to eat?

It is the question that underpins the search to find an answer to the obesity problem: what drives us to eat? No matter what a person’s genetic profile, environment or activity levels, eating more food than what the body needs to meet its energy demands results in just one outcome: weight gain.

Pervasive food marketing and 24 hour access to cheap, energy-dense food are important drivers of making us eat more. Other factors such as lack of sleep, endocrine disorders, air conditioners (which reduce the energy needed by the body to regulate temperature), and even increasing maternal age are just some of a long list of factors that can each explain a small part of the weight gain problem.

Weighing in on the best diet

In the search for the solution to the growing waistlines of Australians, many popular diets have been tried and eventually discarded. There are literally hundreds of dieting books and programs to choose from, with many popular ones substantially departing from mainstream nutrition and medical advice.

So should it be low-fat, low-carbohydrate, high-protein, low-glycaemic index, small meals or any one of a myriad of other popular dieting approaches? The scientific jury is now firmly in with dozens of high-quality randomised controlled trials showing that no one dieting option is the magic solution for everyone.

State of the evidence
Apart from some short-term success for particular approaches, mostly low-carbohydrate diets, all of the popular dieting approaches fare poorly in terms of weight loss, weight maintenance and adherence once the 6-month milestone is passed.

New nutrition guidelines for cancer survivors

There is a lot we know about the best food and lifestyle choices to help someone lower the risk of developing cancer. But what about once a person has cancer? New nutrition and physical activity guidelines give the best advice for what cancer survivors should aim for.

Thanks to earlier detection and much better treatment options, cancer today is certainly not a death sentence. Well over half of people diagnosed will be alive after 5 years.

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