'Tis the season for 'New Year, New Me.'
Whether it's buying a gym membership or starting a diet, millions of Americans are starting their new year with a resolution to lose weight.
However, not all diets are equal.
While cutting back on sugar, high-calorie foods and takeout is unlikely to cause any harm, some of the most popular weight-loss plans in the US come with serious risks.
As the nation's health kick begins, experts are urging dieters to avoid some fad diets at all costs.
They can leave you with serious nutrient deficiencies—and probably won't even help you shed pounds.
Here, nutritionists specializing in weight loss and exercise reveal the three highest diets on their charts.
Celebrity-endorsed juice cleanses can cause serious nutritional deficiencies
Last year, Kourtney Kardashian Barker revealed she was embarking on an Ayurvedic cleanse, which mainly involves liquid meals – she's also endorsed 'detox' juices in the past, including one she created and is sold at the trendy LA supermarket Erewhon
Juice cleanses have long been popular among celebrities and influencers as a way to quickly cut calories.
This diet only involves consuming juices made from fruits and vegetables. It usually lasts for a short period of time, such as a few days or a few weeks.
The Kardashian sisters — reality TV royalty — have been fans of juice cleanses and using “liquid meals” to lose weight and “detox” for years.
Last year, Kourtney Kardashian Barker created a green 'detox' smoothie for LA's luxury supermarket, Erewhon.
The drink contains a combination of antioxidants, electrolytes, coconut yogurt, protein powder and fruit.
Some research suggests that juice cleanses do not result in lasting weight loss
But nutritionist Mark Gilbert, who works in Britain, says juice cleanses have “short-term benefits.”
Although there can be a large calorie deficit, resulting in immediate weight loss, juicing does not provide enough vitamins, minerals, proteins or fats, which are essential for a healthy diet, he says.
“Juice contains virtually all of its calories as carbohydrates, the only one of the three macronutrients that are not as crucial to a balanced diet.”
Without protein, fat or calcium, dieters could experience bone thinning and rapid muscle loss.
Research also suggests that weight loss from a juice cleanse is more likely to be temporary than diets that allow solid foods.
A review from 2017 Current Gastroenterology ReportsFor example, juice cleanses were found to lead to overall weight gain once a person starts eating solid foods again.
And there is no scientific evidence that juice cleanses remove harmful toxins from the body.
CUTTING CARBOHYDRATES CAN INCREASE THE RISK OF CANCER
Cutting out carbohydrates like bread eliminates many essential nutrients and doesn't leave you feeling full, increasing your risk of snacking
Avoiding carbohydrates like white bread and pasta can lead to weight loss – at least in the short term.
“When carbohydrates are replaced with protein and fruits and vegetables, the result can be better body composition and health,” says Gilbert.
However, cutting carbs can have its drawbacks. Eliminating carbohydrates also eliminates foods containing other essential nutrients. For example, whole grain rice and pasta are rich in carbohydrates, but also contain a lot of fiber.
Fiber increases satiety – or fullness – so without fiber you're more likely to go for seconds and overeat. Fiber is also known to support regular bowel movements and reduce the risk of colon cancer.
Research shows that only three percent of Americans get the recommended daily amount of the nutrient: about 30 grams.
The research on low-carb diets like keto – which is low-carb and high-fat – is mixed, although some recent studies have sounded the alarm.
For example, researchers at the University of British Columbia in Canada found that participants who followed a keto diet had higher LDL (bad) cholesterol levels than those who ate normally, which could increase the risk of heart disease.
Additionally, a large-scale 2018 study of low-carb diets in nearly 500,000 people found that this way of eating was associated with a 15 percent higher risk of all-cause mortality, a 13 percent higher risk of cardiovascular death, and an 8 percent higher risk of cancer death. , compared to high-carb diets.
As for weight loss, a low-carb diet is no more effective for weight loss than a low-fat diet, according to a 2018 study of 600 overweight adults.
If you go up and down on the scale, you will eventually gain weight
While Mr Gilbert said yo-yo dieting can be healthy, it is best to stick to a balanced diet and seek professional support such as a dietitian.
Experts have warned against any diet that promises rapid, extreme weight loss. That's because studies show that losing weight this way results in a quick recovery – and often gains more weight than you started with.
The pattern is also known as yo-yo dieting, or weight cycling: the constant back and forth of unintentionally gaining weight and then dieting to lose it.
It has long been criticized as a health hazard because it leads to fluctuating insulin levels, which is necessary to maintain blood sugar levels.
Mr Gilbert said rapid weight loss too often involves removing entire food groups from the diet – which can inevitably lead to nutrient deficiencies.
Additionally, studies suggest that weight loss is not permanent and the practice can lead to lasting health problems.
A 2022 study from researchers at Georgetown University in Washington DC found that rats that restricted their diet for part of the study lost 20 percent of their body weight. However, things returned to normal later.
Both deliberate yo-yo dieters and those who change weight quickly due to a lack of food supply may also be at risk for heart disease, the researchers found.
Study author Dr Aline de Souza said: 'Although the animals look healthy after “recovery” from the diet, their hearts and metabolism are not healthy.
Similar human studies have shown rapid weight gain after one month and, in the long term, an increased risk of developing type 2 diabetes.
In 2013, nutrition researchers at Washington State University stated: 'Diet-induced weight cycling may contribute to metabolic dysregulation and have long-term detrimental effects on the accumulation of visceral adipose tissue. [the type of fat linked to diabetes].
'The success rate is low, with high failure rates, and those patients who achieve weight loss are very likely to regain it.'