Globally, one in eight people are living with obesity. This is an issue because excess fat increases the risk of type 2 diabetes, heart disease and certain cancers.

Modifying your diet is important for managing obesity and preventing weight gain. This might include reducing your calorie intake, changing your eating patterns and prioritising healthy food.

But is one formula for weight loss more likely to result in success than another? Our new research compared three weight-loss methods, to see if one delivered more weight loss than the others:

• altering calorie distribution – eating more calories earlier rather than later in the day
• eating fewer meals
• intermittent fasting.

We analysed data from 29 clinical trials involving almost 2,500 people.

We found that over 12 weeks or more, the three methods resulted in similar weight loss: 1.4–1.8kg.

So if you do want to lose weight, choose a method that works best for you and your lifestyle.

Eating earlier in the day

When our metabolism isn’t functioning properly, our body can’t respond to the hormone insulin properly. This can lead to weight gain, fatigue and can increase the risk of a number of chronic diseases such as diabetes.

Eating later in the day – with a heavy dinner and late-night snacking – seems to lead to worse metabolic function. This means the body becomes less efficient at converting food into energy, managing blood sugar and regulating fat storage.

In contrast, consuming calories earlier in the day appears to improve metabolic function.

However, this might not be the case for everyone. Some people naturally have an evening “chronotype”, meaning they wake up and stay up later.

People with this chronotype appear to have less success losing weight, no matter the method. This is due to a combination of factors including genes, an increased likelihood to have a poorer diet overall and higher levels of hunger hormones.

Eating fewer meals

Skipping breakfast is common, but does it hinder weight loss? Or is a larger breakfast and smaller dinner ideal?

While frequent meals may reduce disease risk, recent studies suggest that compared to eating one to two meals a day, eating six times a day might increase weight loss success.

However, this doesn’t reflect the broader research, which tends to show consuming fewer meals can lead to greater weight loss. Our research suggests three meals a day is better than six. The easiest way to do this is by cutting out snacks and keeping breakfast, lunch and dinner.

Most studies compare three versus six meals, with limited evidence on whether two meals is better than three.

However, front-loading your calories (consuming most of your calories between breakfast and lunch) appears to be better for weight loss and may also help reduce hunger across the day. But more studies with a longer duration are needed.

Fasting, or time-restricted eating

Many of us eat over a period of more than 14 hours a day.

Eating late at night can throw off your body’s natural rhythm and alter how your organs function. Over time, this can increase your risk of type 2 diabetes and other chronic diseases, particularly among shift workers.

Time-restricted eating, a form of intermittent fasting, means eating all your calories within a six- to ten-hour window during the day when you’re most active. It’s not about changing what or how much you eat, but when you eat it.

Animal studies suggest time-restricted eating can lead to weight loss and improved metabolism. But the evidence in humans is still limited, especially about the long-term benefits.

It’s also unclear if the benefits of time-restricted eating are due to the timing itself or because people are eating less overall. When we looked at studies where participants ate freely (with no intentional calorie limits) but followed an eight-hour daily eating window, they naturally consumed about 200 fewer calories per day.

What will work for you?

In the past, clinicians have thought about weight loss and avoiding weight gain as a simile equation of calories in and out. But factors such as how we distribute our calories across the day, how often we eat and whether we eat late at night may also impact our metabolism, weight and health.

There are no easy ways to lose weight. So choose a method, or combination of methods, that suits you best. You might consider

• aiming to eat in an eight-hour window
• consuming your calories earlier, by focusing on breakfast and lunch
• opting for three meals a day, instead of six.

The average adult gains 0.4 to 0.7 kg per year. Improving the quality of your diet is important to prevent this weight gain and the strategies above might also help.

Finally, there’s still a lot we don’t know about these eating patterns. Many existing studies are short-term, with small sample sizes and varied methods, making it hard to make direct comparisons.

More research is underway, including well-controlled trials with larger samples, diverse populations and consistent methods. So hopefully future research will help us better understand how altering our eating patterns can result in better health.

Hayley O’Neill, Assistant Professor, Faculty of Health Sciences and Medicine, Bond University and Loai Albarqouni, Assistant Professor | NHMRC Emerging Leadership Fellow, Bond University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bushfires are currently burning in Australian states including Victoria, Tasmania, Western Australia and South Australia. In some areas, fire authorities have warned residents about the presence of smoke.

Bushfire smoke is harmful to our health. Tiny particles of ash can lodge deep in the lungs.

Exposure to this type of smoke may worsen existing conditions such as asthma, and induce a range of health effects from irritation of the eyes, nose and throat to changes in the cardiovascular system.

Public health recommendations during smoke events tend to provide general advice, and don’t often include advice specifically geared at children. But children are not just little adults. They are uniquely vulnerable to environmental hazards such as bushfire smoke for a number of reasons.

Different physiology, different behaviour

Children’s lungs are still developing and maturing.

Airways are smaller in children, especially young children, which is associated with greater rates of particle deposition – when particles settle on the surfaces of the airways.

Children also breathe more air per kilogram of body weight compared with adults, and therefore inhale more polluted air relative to their size.

Further, children’s detoxification systems are still developing, so environmental toxins take longer to effectively clear from their bodies.

Meanwhile, children’s behaviour and habits may expose them to more environmental toxins than adults. For example, they tend to do more physical activity and spend more time outdoors. Higher levels of physical activity lead to more air inhaled per kilogram of body weight.

Also, a normal and important part of children’s early play is exploring their environment, including by putting things in their mouth. This can result in kids ingesting soil, dust and dirt, which often contain environmental contaminants.

For these reasons, it’s important to consider the specific needs of children when providing advice on what to do when there’s smoke in the air.

Keeping our environments healthy

The Australian government offers recommendations for minimising the health risks from exposure to bushfire smoke. The main advice includes staying indoors and keeping doors and windows closed.

This is great advice when the smoke is thick outside, but air pollutants may still accumulate inside the home. So it’s important to air your home once the smoke outside starts to clear. Take advantage of wind changes to open up and get air moving out of the house with a cross breeze.

Kids are natural scientists, so get them involved. For example, you and your child can “rate” the air each hour by looking at a landmark outside your home and rating how clearly you can see it. When you notice the haze is reducing, open up the house and clear the air.

Because air pollutants settle onto surfaces in our home and into household dust, an easy way to protect kids during smoky periods is to do a daily dust with a wet cloth and vacuum regularly. This will remove pollutants and reduce ingestion by children as they play. Frequent hand washing helps too.

Healthy bodies and minds

Research exploring the effects of bushfire smoke exposure on children’s health is sparse. However, during smoke events, we do see an increase in hospital visits for asthma, as well as children reporting irritation to their eyes, nose and throat.

If your child has asthma or another medical condition, ensure they take any prescribed medications on a regular schedule to keep their condition well controlled. This will minimise the risk of a sudden worsening of their symptoms with bushfire smoke exposure.

Make sure any action plans for symptom flare-ups are up to date, and ensure you have an adequate supply of in-date medication somewhere easy to locate and access.

Kids can get worried during bushfires, and fire emergencies have been linked with a reduction in children’s mental health. Stories such as the Birdie’s Tree books can help children understand these events do pass and people help one another in times of difficulty.

Learning more about air pollution can help too. Our group has a children’s story explaining how air pollution affects our bodies and what can help.

It’s also important for parents and caregivers not to get too stressed, as children cope better when their parents manage their own anxiety and help their children do the same. Try to strike a balance between being vigilant and staying calm.

What about masks?

N95 masks can protect the wearer from fine particles in bushfire smoke, but their use is a bit complicated when it comes to kids. Most young children won’t be able to fit properly into an N95 mask, or won’t tolerate the tight fit for long periods. Also, their smaller airways make it harder for young children to breathe through a mask.

If you choose to use an N95 mask for your children, it’s best to save them for instances when high-level outdoor exposure is unavoidable, such as if you’re going outside when the smoke is very thick.

N95 masks should be replaced after around four hours or when they become damp.

If your child has an existing heart or lung condition, consult their doctor before having them wear an N95 mask.

Our team is currently recruiting for a study exploring the effects of bushfire smoke in children. If you live in south east Queensland and are interested in participating in the event of a bushfire or hazard reduction burn near your home, please express your interest here.

Dwan Vilcins, Group leader, Environmental Epidemiology, Children’s Health Environment Program, The University of Queensland; Nicholas Osborne, Associate Professor, School of Public Health, The University of Queensland, and Paul D. Robinson, Conjoint Professor in Respiratory and Sleep Medicine, Child Health Research Centre, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.