We've heard about the crazy diets Hollywood celebs follow to get in shape for their next movie or even just for a stroll down the red carpet where hundreds of cameras will capture their face and body from every single angle and publish for all the world/internet to see (and dissect). From the watercress soup diet to the apple cider vinegar diet to the cabbage only diet Hollywood A-listers have chowed down on some whacky foods all in the name of keeping their enviable physiques tight. But do they work?

We asked myth-busting, straight talking nutritionist Fiona Tuck, author of The Forensic Nutritionist for her take on the current Hollywood diets trends, which stars follow what diet and whether any of the Hollywood diets will give us regular non-celebrities types the bod of a Tinseltown star. Here's what she had to say:

What are the current diet trends Hollywood stars swear by? 
Vegan: The vegan diet is plant based with plenty of vegetables, legumes, tofu, nuts, seeds and wholegrains. No animal or dairy products are consumed.

Vegan bowl

Macrobiotic: The macrobiotic diet is a way of life. It includes a spiritual part of living and involves eating fresh seasonal produce rich in nutrients which have balanced yin/yang properties. The macrobiotic diet contains foods like whole grains, beans and bean products (like tofu), organic seasonal vegetables, soups, desserts (sweetened with rice syrup, barley malt, fruit and sometimes maple syrup), fish, fruit, pickles, condiments, nuts, seeds and non-aromatic teas.

Paleo/low carb: This diet is about reducing carbohydrate intake to switch the body to burning fat for fuel and is a popular weight loss diet. The diet is high in fats such as nuts, seeds, avocados, oily fish, includes lean proteins such as red meat, eggs, poultry and fish and includes plenty of green leafy vegetables. High starch foods such as rice and potatoes are off the menu. The paleo diet excludes all grains and legumes and only includes foods that were eaten in caveman days.

Which stars follow which diets?

Madonna: Macrobiotic 
Pamela Anderson: Vegetarian 
Ellen DeGeneres: Vegan 
Liam Hemsworth: Vegan 
Uma Therman: Paleo 
Jessica Biel: Paleo 
Kim Kardashian: Ketogenic (a high fat, low carb diet)

 Image: @jessicabiel

Do any of these diets actually work? 
The vegan diet is a plant-based diet, meaning there are no animal products or dairy. By consuming a predominantly plant-based diet, antioxidant and fibre intake is high which is beneficial for gut, heart and hormone health in particular. A diet high in plants has been linked to multiple health benefits including decreased risk of some cancers. The vegan diet needs to be meticulously planned to avoid potential nutrient deficiencies such as low protein, iron, B12 and zinc.

The diets Hollywood A-listers swear by

The low carb diet, paleo or ketogenic diets work particularly well for weight loss and fat burning. Dramatically reducing carbohydrate intake to less than 50g a day takes away the body's instant supply of glucose which shifts the body into a state of ketosis meaning the liver produces ketone bodies to use as fuel. If we are not using carbohydrates for fuel the body has to look for alternate options so we burn fat for fuel. A prolonged state of ketosis can create acidity in the body and may also diminish nutrient and fibre diet. This is not a sustainable diet long term.

What do you consider the most sensible diet to follow? 
There is no quick fix diet that is sustainable long-term. Eating a diet that is full of fresh wholefoods, complex whole grains such as brown rice and legumes, and high in fresh fruits and vegetables is the healthiest diet to follow. The Mediterranean diet is similar to this and it also includes plenty of goods fats such as olive oil - this has proven to be the healthiest diet for disease prevention. My motto is it is all about balance, have a little bit of everything and not too much of any one thing.

Image: Fiona Tuck website

Fiona Tuck's book The Forensic Nutritionist is available now from her website: www.fionatuck.com 
You can also find Fiona on Instagram @fionatucknutrition

The diets Hollywood A-listers swear by