Why your efforts to get a bikini body are doomed to fail
Your best intentions and gym workouts are not enough to shed those pounds. Cherrill Hicks explains what's really holding you back
The start of the summer holidays can come as a mixed blessing. On the one hand, hoorah! But on the other hand, many of us find ourselves staring down the barrel of a week or more on the beach with our wobbly bits exposed to all and sundry.
Why, we wonder, did we abandon on January 2 that well-meaning New Year's resolution to eat more sensibly? And why have we not exactly been getting value for money from our expensive gym memberships? In fact, we may not be wholly to blame.
Research suggests there are many subtle, and often overlooked, reasons why, for most of us, our body goals remain so elusive, despite our best intentions. A nine-year study of more than 278,000 people in England, published in the American Journal of Public Health this month, found that for obese patients, "maintaining weight loss was rare and the probability of achieving normal weight was extremely low".
Previous studies have reached similar conclusions. The reasons, however, are manifold. Here, we look at the unexpected factors that can be making weight loss so difficult.
There's compelling evidence that poor sleep habits can exacerbate weight problems, with one recent Dutch study finding that people who averaged just five hours a night were 73pc more likely to be overweight than their seven- to nine-hour counterparts. It's possible that lack of sleep affects leptin and ghrelin, the two hormones involved in appetite regulation, although it may be that fatigue encourages both over-eating and less physical activity. Getting more sleep is easier said than done, but it's likely to help you stick to your weight-loss plan.
Eating too fast
A 2010 study from Greece showed that those who ate 300ml of ice cream in five minutes had lower concentrations of two hormones released by the stomach after a meal that warn us it is time to stop eating.
"It takes anything between 10 to 30 minutes for our digestive enzymes to release the hormones that tell the brain you feel full after a meal," says Ursula Ahrens, a London-based nutritionist. "If you're eating very quickly, that mechanism might not have kicked in and you may still feel you're hungry."
High stress levels may have you reaching for the biscuit tin, according to scientists from Israel, who say they have pinpointed a "comfort eating" gene that increases the appetite for sweet and fatty foods at times of trouble.
Other researchers argue that stress releases the "fight or flight" hormone cortisol, which can elevate appetite.
But these mechanisms are unproven and it may be that for some, food simply acts as a stress reliever, just like smoking or drinking, according to Ahrens. "It might relate back to experiences as a child - being given a chocolate when you are crying," she says. For most of us, a certain amount of stress is unavoidable in daily life, but relaxing techniques like yoga and mindfulness may help us steer clear of the chocolate.
Lack of sunshine
Could a vitamin D deficiency be to blame for unwanted weight gain?
Scientists from Aberdeen University who studied more than 3,000 women from Scotland in 2008 found those who were clinically obese had vitamin D levels 10pc lower than those of a healthy weight.
Some researchers say that low vitamin D interferes with leptin but it's more likely that obesity lowers blood levels of this vital nutrient.
"Overweight people in general have lower vitamin D status because the vitamin D is bound to adipose [fatty] tissue," says Ahrens.
Experts are divided over whether skipping breakfast helps or hinders weight loss. One 2014 study from Australia suggested that those who fasted between 8pm and noon the next day reduced their waistlines (as well as their risk of liver damage). But other studies show that breakfasting can help keep the weight off. "If you put off eating until you're really hungry you may end up pouncing on a high-calorie snack," says Ahrens.
A busy social life may be thickening your waistline, according to Japanese research that found extrovert men were up to 1.73 times more likely to be obese than their introvert counterparts (while those with anxious personalities were twice as likely to be underweight).
Ahrens is doubtful, saying: "You can also eat quite a lot locked away in your own kitchen. And some people eat less in company."
If you've been pounding away on the treadmill to little obvious effect, you're not alone: a recent article in the British Journal of Sports Medicine argued controversially that while exercise is important for health, it is not the solution for weight loss.
Many people vastly overestimate how many calories they can lose through exercise, says celebrity personal trainer Kathryn Freeland. Worse still, after working out they often "compensate" with a (highly calorific) treat.
"If you do a 30-minute run, you might lose between 300 and 500 calories," she says. "It only takes a Mars bar or two glasses of wine and you're back to square one. People do kid themselves they've done a really tough workout and reward themselves, cancelling out the calories they've just burned."
US research has found little difference in fat loss between women who work out and those who don't. One theory is that after a gym session people cut down on other physical activity.
The low-fat diet has been the cornerstone of eating advice for 40 years, but rising obesity rates suggest it's not effective. Analysis by British newspaper the Daily Telegraph last year found that many low-fat foods promoted as healthy eating contained more sugar than "full fat" equivalents - in some cases more than five times as much.
Official advice is to avoid high fat, processed and deep-fried foods, but experts said the Telegraph's findings showed how "low fat" and "low calorie" products could have more harmful effects than "full fat" equivalents, contributing to rising levels of diabetes, heart disease and cancer.
Why does weight loss become so much harder? Animal studies suggest that menopause causes weight gain thanks to lower levels of oestrogen, which appears to lower the metabolic rate at which the body converts energy. Both sexes lose muscle mass with age and since muscle uses energy to grow, those leftover calories will instead convert to fat. Weight training will help maintain muscle mass and also improve metabolism.
Using plastic to buy food
Research at Cornell University in the US found that paying by card rather than cash encouraged shoppers to indulge in "vice" foods, the theory being that for impulse buys, card payments are less psychologically painful.
The wise approach is to stick to a shopping list of healthy foods - and obey the old adage to never go shopping while hungry.
Eating like an athlete
If you're in training, then surely you need to "carb load"? Actually no; not unless you're a serious endurance athlete doing multiple high-intensity training sessions.
"It drives me nuts to see people consuming the very calories they are trying to burn off," says Freeland.
Are you on the werewolf diet (fasting according to the lunar calendar)? Or the five-bite diet (five bites of whatever you fancy for lunch and dinner)? Maybe you've tried to survive on lemon juice and maple syrup?
Fad diets may work for a short while but your body will soon adjust to famine status, reduce metabolism and retain its fat stores.
"With extreme diets you can override the hunger signals for a while and may lose weight quickly at first but it will be mostly water," says Ahrens.
"Such diets make you feel very unwell because evolution has primed us to eat."