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Losing weight isn’t just about diet and exercise, and gaining weight can have a deeper impact than you may know. These fascinating facts on fat loss give us more insight into how our bodies truly work:
1. You snooze, you lose
Scientists say getting ample sleep should be a frontline defense in tackling obesity. Research shows that inadequate sleep not only correlates with higher body fat, but can also undermine your efforts to lose weight via calorie restriction. Plus, it can cause loss of muscle mass. This is bad news considering the more muscle you have, the easier it can be to lose weight. This vicious combination of undermining calorie restriction and reducing your muscle mass can have serious negative impacts on fat reduction efforts.
Researchers believe this link between sleep and fat stems from the way sleep moderates two hormones: leptin, which makes us feel satiated, and ghrelin, which stimulates appetite. Lack of sleep decreases leptin, leaving us hungry, and increases ghrelin, making us want food. Keeping these hormones in check can help curb overeating. To help do so, ensure you’re getting the recommended amount of sleep someone in your age bracket ought to be getting every night.
2. Get fit, stay fit
Strong, lean muscles aren’t just for gym rats. According to Clean Eating advisor RDN Erin MacDonald, the more muscle you have, the easier it is to maintain and improve upon your fitness level.
“We know that muscle is a much more metabolically active tissue and is directly correlated with your metabolic rate,” said Erin. “The more muscle tissue you have, the higher your metabolism, and the easier time you have losing weight, in terms of body fat.”
One of the major ways your body burns energy is via your basal metabolism – the energy your body consumes by simply existing. Everything you do – walking, sitting, blinking and even sleeping – requires energy, and the energy you expend doing these everyday activities determines your basal metabolic rate. Muscle tissue consumes more energy to exist than fat. Therefore, more muscle means higher metabolic rate.
3. Brain drain
Everybody knows excessive weight can degrade overall health. Obesity is directly linked to higher risk of diabetes, respiratory issues, cardiovascular disease and even cancer. But the impacts don’t stop below the neck.
Higher body fat can affect brain anatomy and, consequently, cognitive function. Studies show that higher body fat can negatively impact subcortical gray matter volume (used for information processing) and hippocampal volume (used for learning and memory). With age, this negative correlation deepens. Another study – one of the largest conducted on obesity and brain function – found that excessive weight gain reduced brain activity and blood flow. Low cerebral blood flow is the primary predictor of Alzheimer’s and linked to mental health disorders like depression, ADHD, schizophrenia and much more.
However, there is some good news. Weight loss has been linked to improved brain health and function. Analyses show that losing excessive fat significantly improved attention, memory, executive function and mastery of language.
4. Acquired taste
Stigma often associates body fat with love of food. But scientists have long known that obesity can actually curb one’s ability to taste, meaning that it’s actually thinner people who may have the ability to enjoy food more intensely. Thanks to recent research out of Cornell University, we now know why.
In a study conducted on rodents, researchers fed one group of mice a lower-fat diet and the second group of mice a higher-fat diet. This resulted in the second group developing obesity. Scientists found that the obese mice ended up with fewer tastebuds. They also had higher levels of TNF-alpha, a pro-inflammatory cell. The greater presence of this cell was upsetting the cell death and renewal cycle of taste buds, meaning obese mice lost taste buds at a higher rate and grew new ones at a slower rate!
We know that excessive fat contributes to chronic inflammation. And now we know that fat-related inflammation not only exacerbates all overlying conditions, but is also responsible for unbalancing the rate of taste bud cell death versus regeneration.
5. It’s hard, and that’s not your fault
Obesity docs see overweight people walk through their doors every day, determined to turn their lives around. Yet within months or a couple years, the weight often creeps back in. For a long time, this regain was hugely stigmatized, tied to perceived lack of willpower and discipline. But recent research argues that the problem is more grounded in human physiology than we knew.
Dr. Joseph Proietto, a researcher from the University of Melbourne, and his team conducted a study on obese patients. Subjects were put on a calorie-restricted diet and assisted in losing weight. But despite long-term efforts and encouragement, the subjects gradually began gaining the weight back.
The research showed that in response to calorie restriction and rapid weight loss, the body rebounded with a defense mechanism armed with hormones. Despite subjects still having significant body fat after dieting, their bodies behaved as if they were starving, with levels of ghrelin (“hungry hormone”) notably higher and leptin (“satiation hormone”) notably lower. While more research is required, this study has evoked much-needed discussion surrounding judgement of heavier people and disturbed conventional notions around dieting.
Eating fewer calories and expending more through exercise are essential steps to weight loss. But you can maximize your efforts by keeping all of the above in mind.
Get the recommended amount of sleep someone in your age range needs. Remember that the more you grow your muscles, the easier you lose the fat. Lose weight not just for your body, but for your brain. And most importantly, keep in mind that weight loss is difficult; it’s not so much one’s discipline that is to blame as it is the body’s physiological response to being in caloric deficit. Your best ammunition against this is prioritizing good habits like clean, whole foods, ample sleep, exercise and a perseverance mindset.