Those looking to lose weight must eat fruit and vegetables to avoid falling into an unsustainable crash diet, an expert has said.

Professor of nutrition and author of the Instinct Diet Susan Roberts told the Irish Independent that healthy eating and "good crash diets" were not necessarily incompatible.

She described a good crash diet as being sustainable, in which case people could eat as little as 1,200 calories a day.

Instead of getting those units through special shakes, maple syrup or lemon water fad regimes, get them through fruit, vegetables, soups and foods with fibre, Ms Roberts advised.

Her comments came in response to the high-profile death of a Leeds bride-to-be, who died from heart failure after following a strict LighterLife plan which featured no fruits or vegetables.

"Bad crash diets are diets you can’t keep up or are unhealthy if you do," the nutritionist explained.

One diet idea that has recently garnered some media attention is the grape diet, believed to help promote longevity and weight loss.

Isabel Carter

A new beauty trend has seen experts recommending putting fruit both on the table and on the face for conditioned skin.

Writing for business magazine City A.M, Zoe Strimpel tried this recent craze and raved about its effectiveness.

"My face [was] looking and feeling the best it has done, perhaps since babyhood," she explained.

This craze was launched by American skin specialist Dr Alkaitis, who uses fruit, vegetables, yogurt and plants – anything that is living, edible and has skin benefits.

"If your body can absorb it happy and gratefully, your skin can to," Ms Strimpel added.

Among recipes to try is a citrus fruit mix for the legs and feet.

The treatment is composed of a foot bath with lemon and lime slices, followed by a lemongrass scrub, a rosemary oil massage and then a zest and peppermint mask.

This mix is thought to improve circulation and make for a smoother silhouette.

Consuming vitamin C was recently found by scientists at the University of Leicester to be beneficial to the skin.

The nutrient helped skin recuperate after sun exposure and resist the effects of aging longer.

Bruce Malone

The longevity of Water Breuning, the world’s oldest man at 113, could be partly attributed to the amount of fruit he eats daily.

"I eat a lot of fruit every day," he told the Great Falls Tribune.

The Montana resident also recounted eating the governor’s gift of a fruit basket in one go.

"Boy, I tell you that was good fruit. I ate the whole darn thing," the record-holder asserted, adding: "Peaches, pear(s?), everything – it sure was good."

Among Mr Breuning’s other secrets is skipping dinner.

Indeed, he has not eaten an evening meal since 1978 and believes everybody should do this.

"[People] just eat too much," he complained.

The only medicine he takes is a baby aspirin daily and he drinks lots of water.

Scotland’s oldest woman died last year aged 110 and also reported eating fruit every day.

Marjorie Macgown further said a daily dram of malt whisky was de rigueur for longevity.

Bruce Carter

A doctor has warned against choosing to get a vitamin C kick from juice instead of an orange or another fruit or vegetable.

Dr Phil Wagner said orange juice can have excessive amounts of sugar, which will compete with vitamin C to enter cells.

"The best approach is doing simple things such as … eating a healthy diet of five fruits and vegetables," he explained in the Palo Alto Daily News.

Dr Wagner went on to remind readers that vitamin C had many qualities and should be consumed daily.

Recently, researchers at the University of Leicester and Institute for Molecular and Cellular Biology in Portugal discovered this nutrient contains elements capable of helping regenerate and improve the quality of skin.

The previously undiscovered property could improve on the natural damage caused in old age and repair damaged skin after sun exposure.

Oranges, kiwi fruits and apples are all produce containing high levels of the vitamin.

Noel Plumbly

When it comes to eating well, consumers have been sidelined by elaborate health foods when all they have to do is "eat a piece of fruit", a health specialist has said.

Gail Underbakke, nutrition coordinator of the University of Wisconsin Health’s preventative cardiology programme, suggested people have skewed conceptions of what food is good for people.

Speaking at the university’s lecture series entitled In Defence of Food, she asserted this could be because of the aggressive marketing behind what she called "functional foods".

These products will often bolster too-good-to-be-true claims of dietary advantages with dubious research and slick advertising, the expert claimed.

Ms Underbakke pointed out that at the end of the day, these were processed foods after all.

"We have come so far away from basic food that if it doesn’t have a shiny cover and it’s not perfect, we do not think that it is good enough," she added.

One recent example of this was a ruling by the Advertising Standards Agency finding This Water was misleading consumers with claims of being simple and natural.

The rejection was based on the discovery that each bottle contained between 33.6 and 42 grams of sugar.