Five Guys might not be the first place that comes to mind when looking for a healthy, balanced meal - but its new lettuce wrap could help dieters stay on track.
The fast food chain has launched a new sub-250kcal bunless hamburger targeted at people who are looking to lose weight this January.
John Eckbert, chief executive of Five Guys Europe, said the lettuce wrap - which packs in 24g of protein per beef patty- is the 'perfect combination of fresh-flavours and guilt-free enjoyment', making it a 'great balanced alternative for GLP-1 users.'
The new wrap is marketed alongside Coca-Cola Zero Sugar and is aimed at calorie-conscious consumers, who are looking to prioritise nutrient dense toppings, like onions and tomatoes, over refined carbohydrates.
Five Guys believes the £10-bundle will help people more easily hit their protein goals, whilst cutting back on added sugar, without having to compromise on flavour.
We asked registered nutritionist and author of The Low Appetite Cookbook, Rob Hobson for his verdict to learn whether the bundle really is a nutritious option for the more health-conscious among us.
'The lettuce-wrapped burger is often positioned as a "healthier" choice, and nutritionally it does offer some positives like being high in protein and lower in calories and refined carbs than a standard burger, which may suit January dieters and some people using GLP-1 medications,' he said.
Around 2.5million people are currently thought to be using GLP-1 weight loss jabs, such as Wegovy and Mounjaro, which work by mimicking hormones released after eating to promote feelings of fullness.
This in turn lessens appetite, and as a result many users express wanting to fill-up on more nutrient-dense, low calorie foods that help keep digestion moving.
To lose weight on these medications, users must also stay within a calorie deficit - expending more calories than they digest - which is why the fast food chain has opted for a lettuce wrap over a bun and a zero-calorie drink option.
But, according to Hobson, the patty itself could cause digestive issues.
'Protein is essential, especially when appetite is reduced,' he explains, 'but a burger isn't the only or necessarily the best way to get it.
'There are plenty of healthier, more digestible protein options that deliver the same benefits with less fat and a broader range of nutrients.'
According to Five Guys' UK nutrition guide, a classic beef burger patty contains a whopping 14g of fat - 5.6g of which is saturated.
Whilst a small amount of fat is an essential part of a healthy, balanced diet, helping the body absorb essential vitamins - but too much saturated fat can raise so-called 'bad' cholesterol levels, increasing the risk of heart attack and stroke.
According to official NHS guidelines, men should eat no more than 30g of saturated fat a day, whilst women should have even less at 20g a day.
Aspartame, an artificial sweetener found in Coca-Cola Zero Sugar, has been linked with heart and brain damage, as well as high blood pressure, stroke and even cancer
Hobson added that whilst Five Guys offers a range of toppings that can help boost the nutrient content of the wrap, its vegetable options are 'fairly limited and mostly low in fibre and micronutrients.'
He said: 'Whilst lettuce, tomato and pickles do add freshness, they don't significantly boost nutritional value in the way more substantial vegetables, legumes or wholegrains would.
'So from a nutrient-density point of view, it's still a protein-heavy, relatively one-dimensional meal.
'For people on GLP-1s, digestion also matters. These medications slow gastric emptying, so even without the bun, a burger patty can feel heavy or trigger nausea for some, particularly if it's high in fat.
'Others may find that if eaten slowly and kept simple, it may work occasionally but it's not automatically "GLP-1 friendly" just because it's low carb.'
The nutritionist concluded: 'Ultimately it can be a better choice than a full burger and fries, but it shouldn't be mistaken for a nutritionally complete meal.'
And, just because Coca-Cola Zero Sugar doesn't contain any added sugar, it doesn't mean it's good for you, Hobson added.
Last year, regularly consuming fizzy drinks laced with artificial sweeteners, like Coca-Cola Zero Sugar was linked with an increased risk of heart and brain damage.
The new bundle sees the classic burger bun swapped for a lettuce wrap - with the option to add up to 15 free toppings
Aspartame had previously been linked to health concerns including cancer, high blood pressure and stroke.
But last month, Spanish researchers said consuming high levels of the additive may also age the brain and stiffen the heart.
The fast food giant is just one of the many food producers who are expanding their offerings to cater for weight loss drug users.
Earlier this month, Marks and Spencers launched a new range of 'nutrient dense' products, 'perfectly portioned' for fat jab users.
However, questions are still being raised about the side-effects of GLP-1 medicines.
These include nausea, vomiting, bone damage and even organ damage - all of which put added strain on the body, making it hard to get vital nutrients and minerals.
Last week, experts warned that weight loss jab users may have to stay on the drugs for life, after a landmark study found that most users regain weight four times faster than people who use dieting and exercise alone after coming off the jabs.