Weight loss | August 31, 2017 | Author: Naturopath
This isn't your average calorie-counting article. Weight loss is big business and a multi-million dollar industry, but shredding fat isn't the only reason why you might want to keep an eye on calories. Maintaining weight or even gaining weight is an important part of staying healthy as we age, or when living with certain diseases like cancer or multiple sclerosis. Just like losing weight can be a step towards health for some people, putting on weight can be part of another's healing journey. And as far as aesthetic go, bulking up is as popular as slimming down these days.
There's a lot of information out there about calories and weight management.
Calories and kilojoules are types of measurements for the same thing – a unit of energy. Our bodies acquire energy (or calories) from food and then use that energy to fuel body processes that keep us alive. It's that simple.
The fundamentals of weight maintenance are easy to understand – an equilibrium of calories in and calories out is required to maintain body weight.
When calories in is less than calories burned, the body breaks down energy stores (like fat and muscle) for fuel and this results in weight loss.
Everybody's metabolic rate is different, so we also need a different number of calories to give us enough energy. The word “metabolism” refers to how many calories your body uses when at rest.
The process of eating, absorbing, and eliminating food requires a lot of energy. This natural calorie-burning activity is called the “thermic effect”. All movement involved in eating and digesting uses calories, from chewing food through to the churning of the stomach and movement of the intestines.
A rough estimate suggests that the thermic effect burns 10 percent of calories eaten. But different foods require more energy than others – protein-heavy foods burn the most calories, with a thermic effect of 30%; fibrous fruits and vegetables come in second with a thermic effect of 20%; and the digestion of fats burn the least calories, with only 3% being used by the thermic effect.
Some diet gurus have suggested that coconut oil has a higher thermic effect than other oils, but recent has almost busted that myth – it has the same thermic effect as corn oil, at least in the short-term .
Thoroughly chewing food before swallowing it also increases the thermic effects of any meal, and can reduce appetite after eating . Chewing gum is also a calorie-burning activity, but beware that chewing too much can cause diarrhoea!
Most body processes continue during sleep, and some even ramp up their activity as we snooze. We are constantly burning fats and sugars to supply energy for cell repair, pumping blood, supplying to brain with the nutrients is needs to keep us asleep, and maintaining the body's internal temperature.
We burn fewer calories while we sleep, but that doesn't mean staying awake will have a long-term calorie loss. The body is hardwired to hold onto fat if it detects significant sleep deprivation. Having late nights and experiencing sleep loss has been shown to influence food decisions during the day, making you more likely to eat unhealthy calorie-dense foods and simple carbohydrates  .
Remember when we said that calories are heat? The body burns more calories to keep warm in cool temperatures and it even grows more tissues to up-regulate the process. “Brown fat” is a type of fat that creates more heat than any other organ in the body, and it burns more calories to do so. It is abundant in babies but shrinks as we grow older, but recent research has discovered that it can actually grow back to help regulate body temperature. In a 2014 study, it was found that sleeping in colder temperatures promoted brown fat and burned more calories .
The cardiorespiratory system is a big consumer of calories. It's no secret that aerobic exercise burns calories, but anything that increases your heart-rate even slightly will up your energy usage by putting more demand on your cardiorespiratory system. Contraction of the heart muscle, movement of the diaphragm, and the exchange of gas and nutrients from the blood requires a lot of energy.
There's a catch though – stress hormones. Watching a pulse-racing horror movie might burn more calories than a rom-com, but the net effect won't necessarily be weight loss . Stress hormones like cortisol are released when we're scared or anxious, and they tell the body to hold onto fat in the long-run, increase our appetite, and do everything they can to get the energy back that the increased heart-rate burned.
Muscle burns more energy than fat, so the muscle:fat ratio of the body also impacts the resting metabolic rate. The more muscle you have, the faster your metabolism and the more calories you'll burn even when you're not moving. This is because muscle fibres have a higher metabolic rate than fat cells – they convert calories to energy more quickly and frequently than fat cells do.
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 LaBarrie, J. & St-Onge, M. P. (2017) A coconut oil-rich meal does not enhance thermogenesis compared to corn oil in a randomized trial in obese adolescents. Insights Nutr Metab., 1:1, 30 - 36. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5531289/
 Komai, N., et al. (2016) Thorough Mastication Prior to Swallowing Increases Postprandial Satiety and the Thermic Effect of a Meal in Young Women. J Nutr Sci Vitaminol (Tokyo), 62:5, 288 – 294. https://www.ncbi.nlm.nih.gov/pubmed/27928114
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