A diet shake up and exercise is usually the go-to approach for those seeking to shift the scales.
But while this usually means cutting out the junk food and packing in the fruit, veg and whole grains, others prefer a more extreme option.
Just type in #weightloss on any social media platform today and you’ll be met with everything from intermittent fasting diets, juice cleanses and detox teas to anti-inflammatory diets.
Yet, research has suggested that up to 97 per cent of dieters regain everything they have lost within three years.
In 2025, many hoping to shed the pounds may turn instead to Ozempic, Mounjaro and other so-called ‘skinny jabs’.
The injections have been hailed a breakthrough in the war on obesity. However, their eligibility criteria is strict and waiting list long.
Here, MailOnline has analysed five of the most popular weight loss plans available to Brits to assess which is the most cost effective way to actually lose weight.
The injections, like Ozempic and Wegovy, are designed to help type 2 diabetes patients control their blood sugar levels or for obese people to lose weight for health purposes
Weight loss jabs
How it works: Self-injected once a week.
Semaglutide, sold under the brand names Ozempic and Wegovy, mimics a hormone called GLP-1 that makes people feel full.
Mounjaro, which contains a more powerful ingredient tirzepatide, also mimics GLP-1, as well a second appetite-controlling hormone called GIP.
Cost: A month’s supply of semaglutide is available privately in the likes of Boots and Superdrug for around £200.
Eligibility criteria for people wanting the get the drug on the NHS — for the standard prescription rate of £9.90 in England — is strict.
Mounjaro was given the green light for NHS use last year. However, the NHS drugs watchdog NICE say it could take 12 years for everyone to receive it.
Privately, one month’s supply costs around £180.
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How effective it is: Trials pivotal to getting Novo Nordisk’s semaglutide approved show it can help users shed up to 15 per cent of their body weight over 68 weeks.
Studies have found Mounjaro, made by US pharmaceutical giant Eli Lilly, could help obese people lose up to 22.5 per cent of their body weight in 72 weeks.
Side effects, however, can include nausea, diarrhoea, vomiting — which usually goes away over time — and constipation.
Research also suggests that, in rare cases, GLP-1 drugs can trigger pancreatitis, a potentially fatal swelling of the pancreas gland.
Roughly one in every 1,000 patients on Ozempic or Wegovy, which both contain the same active ingredient, semaglutide, will develop the condition.
In trials of Mounjaro, around 23 out of every 1,000 patients developed pancreatitis.
In September, Scottish nurse Susan McGowan, 58, died from multiple organ failure, septic shock and pancreatitis after taking just two doses of Mounjaro.
Experts say it will be important to monitor patients for these rare side effects, but argue that all medicines have complications.
WeightWatchers pushes well-balanced meals full of protein, fruits, vegetables and nutrients, but the company is adamant that no food is off-limits
WeightWatchers
How it works: Over five decades, WeightWatchers has built its global success on the premise that healthy controlled eating and iron willpower are the key to achieving sustainable weight loss.
It offers membership plans that offer support and recipes to help slimmers lose weight, giving members points budgets to stick to.
One programme is even designed specifically for people using appetite curbing injections.
Users input what they’re eating into an app, which takes the food’s calories and nutritional information to turn it into a WeightWatchers point value.
Cost: Under a 10-month subscription plan, users pay £10 for the first 10 months, then a standard monthly price of £18.95.
This plan includes a nutrition plan, trackers, and over 4,000 recipes for meal inspiration.
How effective it is: WeightWatchers pushes well-balanced meals full of protein, fruits, vegetables and nutrients, but the company is adamant that no food is off-limits.
One 2017 study published in The Lancet found participants on the programme lost an average of 4.75kg after 12 weeks and 6.76kg after a year.
However, experts have previously warned that the low point scores promoted by WeightWatchers with certain foods don’t always equal high nutritional value.
Others have cautioned that weight loss through calorie-restricted diets is not often sustained.
The ZOE diet, created by renowned expert Professor Tim Spector and team, helps people feel and sleep better, too
ZOE issues advice based on the user’s ‘unique biology’ and promises to improve long-term health through a series of small, smart dietary changes
ZOE
How it works: The personalised regime is based on results of poo and blood samples.
No food is ‘off limits’ under ZOE’s programme, which instructs users not to worry about calorie counting. Instead, it aims to create sustainable eating habits.
Typically, users are recommended to shun large amounts of dairy, processed carbs and alcohol.
They are advised to tuck into fermented and high fibre foods, including oily fish, wholegrains, nuts, seeds and pulses.
Cost: The at-home test kit costs £299 for slimmers to take poo and blood samples.
These are sent to a lab to calculate blood fat, blood sugar, and gut microbiome levels before personalised food scores are created.
Each food is given a 0 to 100 rating, based on how their body processes it, where 0 is positively damaging and 100 the best it can be.
The app, which charges between £25 to £35 per month, depending on the type of membership selected, then offers users personalised diet and lifestyle advice.
How effective it is: Studies suggest the ‘anti-diet’ has helped wannabe slimmers lose more than two inches off their waist in just 18 weeks.
The diet, created by renowned expert Professor Tim Spector and team, helps people feel and sleep better, too.
According to research published in the journal Nature Medicine last year, as well as losing 6.3cm off their waist, participants who stuck to the ZOE strategy shredded 4.7 per cent of their weight (4.78lbs or 2.17kg), on average.
However, ZOE app users have complained that the strict timings and rules around what you eat and when you initially take the blood tests can be complicated.
Others love it and have credited it with solving their weight issues. But some have also said that while they began well they did eventually relapse into old patterns.
SlimFast has formulated a routine for those who love to eat little and often. With a simple daily routine combining conventional foods and diet products, the company promises results through a variety of different programmes
SlimFast
How it works: Breakfast and lunch are replaced with SlimFast shakes or bars.
A conventional cooked meal for dinner is allowed. But this should not exceed 600 calories for women and 800 calories for men.
Three snacks are also allowed each day of up to 300 calories combined.
Cost: Roughly £3.50 per day excluding dinner
How effective it is: Eating six times a day while on a diet isn’t the most common tactic used to lose weight.
But SlimFast has formulated a routine for those who love to eat little and often.
With a simple daily routine combining conventional foods and diet products, the company promises results through a variety of different programmes.
Including the normal meal for dinner, this averages dieters daily intake to an unforgiving 1,300 calories.
Under the plan, three snacks are also allowed each day of up to 300 calories combined
For those who struggle with their energy levels, SlimFast also offers a keto version of their programme.
Advocates say keto diets encourage ketosis, which is a metabolic state that occurs when your body burns fat for energy instead of glucose.
But experts have long warned that while SlimFast may provide an easy short-term solution, it is not always the best long-term investment.
One study found that those in the SlimFast group had lost an average of 10.5 pounds (4.8 kg), or 4.9 per cent of their body weight, after 6 months.
However, almost a third (29 per cent) of participants dropped out of the study because they couldn’t tolerate the diet, and only 9 of the original 58 participants were able to maintain the diet for 12 months at follow-up.
Other experts have previously warned that strict keto diets could could trigger low blood pressure, kidney stones, constipation and nutrient deficiencies.
Participants are given a low-calorie, nutrient-complete soup and shake diet, totalling around 800 calories per day, for between 12 and 20 weeks
The Cambridge Weight Plan
How it works: The Cambridge diet – which has been rebranded as the 1:1 diet – remains one of the most restrictive diets out there.
Participants are given a low-calorie, nutrient-complete soup and shake diet, totalling around 800 calories per day, for between 12 and 20 weeks.
They also get support from a nurse or dietitian to reintroduce healthy foods and maintain weight loss, while medications for type 2 diabetes and blood pressure are stopped if deemed safe.
Cost: It is offered on the NHS or through a private consultant.
Since its launch in 2020, roughly 25,000 people have been offered the NHS soup and shake programme, with the number expected to double in the next five years.
Adults who have been diagnosed with type 2 diabetes in the last six years and have a BMI of over 27 are eligible for the programme.
According to the Cambridge Weight Plan, the cost per week for the diet is around £62.79 based on 3 meals a day.
Almost 4.3 million people were living with diabetes in 2021/22. And another 850,000 people have diabetes and are completely unaware of it
How effective it is: Soup and shake schemes have long drawn criticism from experts for being unsustainable.
However, The Cambridge Weight Plan approach offered on the NHS was last year hailed as ‘life-changing’.
The first analysis of the NHS’s implementation of the soup and shake diet last year, found that a third of type 2 diabetes patients who followed the diet for a year lost weight and were in remission.
However, only 12 per cent of those who embarked on the brutal diet managed to stick to it for a full year.
It means that, in total, only 3 per cent of patients who tried the diet actually achieved the desired result.
Of the 945 people went on to complete the diet for a year, on average they lost 15.9kg.
The NHS said very low calories diets, that involve eating 800 calories per day or fewer, should only be followed under medical supervision and for a maximum of 12 weeks.
