Do New Year's diets actually work?

Why do people start diets in the New Year?

The festive season is a period of rest and relaxation for a lot of people. It's a time to unwind with loved ones, as well as enjoy delicious food. This can cause people to feel guilty for 'overindulging' and feeling like they've put on weight. As a result, as soon as the New Year strikes, they're looking for instant, dramatic results to shift the weight they've gained, with a diet seeming like a 'quick fix'.

Fitness expert Penny Weston says that in January she often finds people starting 'crash diets', which tend to be unhealthy with unrealistic, unsustainable results.

She says people tend to start diets at the start as opposed to the middle of the year, because they regard the new year as 'a time for change'.

"People often feel more motivated to make lifestyle changes in the New Year after reflecting on the past 12 months and setting goals for the year to come. People make New Year's resolutions that involve diet and fitness in a bid to overhaul their looks or overall health."

Examples of New Year diets may include:

• Atkins.

• Keto.

• Vegan.

• Paleo.

• Low-carb.

• Low-fat.

• Intermittent fasting.

It's common for people to also sign up to weight loss programmes, such as Weight Watchers (WW), or join health coaching and calorie tracking apps, such as Noom.

Are diets started in the new year actually sustainable, or are they destined to fail?

Typically, people tend to last a few months on a diet - even less if it's really strict. One problem with this, however, is people view 'giving up' on their diet as a form of failure. They believe that they have failed at the diet, rather than the diet failing them and their bodies. This leads to an endless pursuit of the 'perfect diet'.

Weston adds that dieters tend to lose momentum as they gradually realise how unsustainable their diet is.

"People usually slip back into old habits when they aren't getting the correct balance of nutrients to keep them feeling full and energised. They then start snacking and eating calorific foods again, proceeding to punish themselves for not having the 'willpower' to diet, even though the diet wasn't built to last in the first place," she says.

"Whether or not New Year diets are actually sustainable depends largely on the diet itself, rather than the time of year it's started. I believe that fad and crash diets are always destined to fail, no matter the time of year."

A 'crash diet' is a weight-loss diet undertaken on a short-term basis with a sense of urgency, as a person aims for rapid results. While crash dieting can provide short-term results by cutting calories, there are a lot of health problems with this approach to weight loss.

The issues with crash diets

They make you hungry

If you are drastically cutting down your calorie intake to an amount your body isn't used to, it will only make you more hungry. This can lead to episodes of binge eating and cravings for the specific foods you are depriving yourself of (much like, when you're a child and your parents say you aren't allowed sweets, you only want them more).

They can be bad for your heart

Crash dieting can lead to heart problems, especially if you already have a heart condition. A 2018 study followed 21 volunteers who were classed as obese, with an average age of 52. Participants consumed a very low-calorie diet for eight weeks.

After one week, total body fat, visceral fat and liver fat had all significantly fallen, and participants had improvements in insulin resistance, fasting total cholesterol, triglycerides, glucose and blood pressure. However, also after one week, heart fat content had risen by 44%. This was associated with a deterioration in the heart's ability to pump blood.

They slow your metabolism

Having a high metabolism allows your body to burn calories at a faster rate while resting. However, restricting your calories can slow this down as your body tries to preserve energy.

They encourage a toxic attitude towards food

Crash diets are not healthy for your relationship with food, and can lead to disordered eating habits. Forcing your body into periods of starvation as an act of punishment can warp your mindset around food, viewing certain things as 'good' or 'bad', and ultimately distort your perception of self-worth depending on what you eat. Crash dieting also encourages obsessing over food.

They often reduce your energy

Particularly if you are limiting your intake of carbohydrates - which are the brain's preferred source of energy - it's likely dieting will make you feel tired and weak. Dizziness is also common. Research has actually found that eating the equivalent of 7.5 slices of wholegrain bread per day is linked with 'optimal' health outcomes.

They can cause your mood to suffer

Most of the foods you are restricting while crash dieting are probably things you enjoy. Therefore, it's understandable why crash dieting makes you miserable. Severely restricting calories can cause you to become irritated and cranky, with low concentration or interest in everyday tasks.

They can cause hair loss

What you eat helps keep your hair healthy. Therefore, depriving your body of protein, healthy fats, vitamin C and E and zinc can lead to hair damage and hair loss.

"I actually hate to even use the word 'diet' and prefer to see what we eat as nutrition and fuel for the body. By doing this and learning to embark on a nutritious food plan that is incorporated with fitness, the results are not only more effective but healthier and more sustainable in the long term," says Weston.

Over an extended period of time, persistent dieting can actually affect the menstrual cycle or stop periods altogether. Restrictive diets can also affect fertility.

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How can you improve your health in a more sustainable way?

Weston wants everyone to understand that improving one's health isn't just about losing weight, and weight varies hugely from one individual to another. Some people are actually healthier for gaining weight.

"There are obviously official weight and BMI guidelines that give an indication of what our ideal weight range is, but even these vary depending on a person's muscle make-up, build and genetics," she says.

Therefore, if you are dieting with the intention of losing weight, it's crucial you aren't basing your 'dream body' on someone else's because, even if you eat everything that they do, you will not look like them. Human beings are all unique with different needs, needs we must meet if we want to be truly healthy. You can be the thinnest person in the room but, if your body is undernourished and fatigued, not only are you likely to be unhealthy, you'll be unhappy too.

While weight loss is not inherently bad, you should question your reasons beforehand and ensure you have a long-term plan that will be kind to your body and good for your mental health.

Weston says, "In order to reach and sustain a healthy weight, whatever that may be, the most sustainable way to achieve it is through a combination of fitness, lifestyle and nutrition changes, rather than a faddy diet. Regular exercise and eating a balanced diet are the key to losing weight in a sustainable way. This means keeping a check on portion sizes, cutting down on high-fat, high-salt processed and high-sugar foods, and eating more lean proteins.

I'm a firm believer in eating a healthy diet rich in all the essential nutrients that come from plant-based goodness, such as lots of fruit, vegetables, grains, pulses and plant-based proteins. This, combined with a manageable, realistic exercise regime, is a far healthier way to achieve a maintainable weight."

Where can you seek support if you want advice on your diet or weight?

"Fortunately, there is now a lot of advice online about dieting; however, there's also so much information about weight and body image that it can negatively affect your confidence and self-esteem. Not to mention the fact that so many images on social media are airbrushed or filtered, so the body ideals many people are striving for are unobtainable," explains Weston.

For professional advice on diet, weight or body image, she recommends seeking the help of a qualified and experienced practitioner, whether that be your GP, a dietician or a qualified fitness expert. They can advise you on healthy changes to make for your diet and physical activity that are achievable and sustainable.

Additionally, if you do wish to research dieting and fitness online, make sure your resources are trustworthy and accurate. Particularly on social media, a lot of companies will promote weight loss products as a 'quick fix' (such as detox teas and weight-loss shakes) to earn money. You should only take health advice from those qualified to offer it. You can also access a variety of information on Patient.info relating to weight loss and dieting, which is all reviewed and clinically approved by a GP.