There’s a lot to be said for slow, steady weight loss, but if you’re looking to kick-start your diet or slim down for a holiday, nutritionist Fiona Kirk’s new diet plan, based on 
the latest fat-burning research, may be your go-to guide.

By following her rules as well as 20 research-backed diet and lifestyle changes, you’ll be well on your way to a slimmer you by summer.

fastest way to lose weight

The fastest way to lose weight

The plan recommends 20 research- backed diet and lifestyle changes. Think about increasing your fruit and veg intake, cutting out fizzy drinks, reducing starchy carbs and including protein in every snack and meal.

MORE: 500 calorie meal plans for the 5:2 diet

For maximum results, Fiona recommends you make 
as many of the changes as possible in the two-week period. The book also offers a 14-day meal plan if you would prefer to follow her diet to the letter.

Here are some of the diet’s essential 
tips for fast, achievable weight loss:

  1. Rethink breakfast
    ‘There is scant evidence to prove skipping breakfast results in us eating more during the remainder of the day,’ says Fiona. ‘Have your first meal of the day when you are actually hungry.’
  2. Go pink
    Japanese researchers showed 
that mice given astaxanthin – the pigment that gives salmon and prawns 
its pink colour when cooked – had significantly lower body weight and 
body fat than mice fed a similar diet without astaxanthin. ‘Add a portion 
of pink into your day,’ says Fiona.
  3. Try a bedtime snack
    ‘Studies show that those who get less than six hours’ sleep per night tend to gain more weight than people who get seven to eight,’ says Fiona. Try 
a snack that promotes the release of the sleep hormone melatonin 20 minutes before bed – such as half a banana or two buttered oatcakes with two turkey slices.
  4. Rev up weight loss
    ‘Caffeine increases the number of calories the body burns at rest,’ says Fiona. ‘A single 100mg dose may increase our metabolic rate by 3-4% for 
at least an hour and a half afterwards.’ 
It’s particularly effective before exercise – so have a double espresso or small filtered coffee first thing (no milk or sugar), followed by 30-45 minutes 
of exercise, then a glass of water.
  5. Fight fat with calcium
    A growing body of evidence indicates that a diet rich in calcium allows us to burn more calories per day,’ says Fiona. ‘There’s also evidence that when calcium levels are low, the brain detects this and stimulates feelings of hunger, causing us to eat more.’ Fiona recommends that we regularly eat nuts, seeds, spinach, cabbage, broccoli and beans, which also provide magnesium.

MORE: Susanna Reid’s diet secrets revealed as Good Morning Britain host sheds TWO stone

fastest way to lose weight

The fastest way to lose weight: your fast-lane meals

Cleansing juice: Mix equal parts of water, unsweetened grapefruit, pomegranate and cranberry juices. Add a pinch of cinnamon, ginger and allspice and stir well.

Overnight muesli: Simply combine 6tbsp oats, 140ml coconut water, 2tbsp flaked, toasted almonds, ½tbsp Manuka honey, 1tbsp full-fat Greek yogurt, 2tsp fresh lemon or lime juice, half a peeled, cored and grated apple and 4 finely chopped fresh mint leaves. Mix well, cover and chill overnight. Serve with a sprinkling of cinnamon.

Crispbreads: Top 2 plain, rye or seeded crispbreads with one of the following:

  • Fresh prawns or crabmeat, sliced cucumber, chopped boiled egg, natural yogurt and toasted pine nuts.
  • Smashed avocado, cottage cheese, grated courgette, cherry tomatoes 
and a spoonful of mango chutney.
  • Sliced cooked beef, tzatziki, toasted flaked almonds, mint leaves and honey.

Quinoa Thai Veg Bowl: Combine 50g cooked quinoa, 
4 chopped broccoli florets and 
½ finely sliced red onion with a small grated carrot, 1tbsp chopped fresh coriander leaves, 2 finely sliced spring onions and 1tbsp fresh peanuts. Make a dressing with the juice and zest of half a lime, ½tbsp each of tamari, sesame oil and rice vinegar, 1 garlic clove and 2cm piece fresh ginger (both peeled and grated). Stir into the quinoa mix, season and scatter over with some sesame seeds.

Serve with: Orange smoothie
Blitz 3 ice cubes, 1 yellow or orange pepper, 1 orange, ½ cantaloupe melon (all peeled and chopped), 4 fresh apricots (stoned and chopped) and 
4 cos lettuce leaves until smooth. Add 
2tbsp coconut milk and fresh carrot juice. Blitz as desired.


  • One-pot chicken/fish/chickpeas: 
Preheat oven to 220C/Gas 7. Spread 200g diced sweet potato and 3 unpeeled garlic cloves over the base of a deep roasting tin. Place 2 chicken thighs (skin-side up) on top. Pour in 40ml chicken or veg stock, pop 2 lemon wedges around tin, drizzle over 1tbsp olive oil, and season. Place tin (uncovered) in the middle of oven for 20 mins. Remove the tin from the oven. Add 1 diced courgette, half a finely sliced and deseeded red chilli and 50g sliced chorizo. Mix well, but keep the chicken on top. Return to the oven for 20 to 30 mins or until the chicken is cooked through and veg is cooked, but still has bite. Remove tin from oven, squeeze garlic cloves from skins, mix through, discard skins, then stuff ½ small bag spinach leaves and 1tbsp chopped parsley in and around everything. Return to oven for 5 to 10 mins before serving. Serves 2.
  •  If using fish (2 white fillets) or chickpeas (½ x 400g tin, drained and rinsed) instead of chicken, wait until 15-20 mins before the end of cooking time before adding. Omit chorizo if you don’t eat meat.
  • Super-quick salmon: Brush a salmon fillet or salmon steak with olive oil and grill under a moderate heat for 7-8 mins, turning only once. Sprinkle with Worcestershire sauce or balsamic vinegar and lime or lemon juice before serving with at least 3 steamed or roasted vegetables or a lightly dressed mixed salad.
  • Stir fry tofu: Cut 2 x 1in slices of tofu into cubes and stir-fry quickly in a little olive oil mixed with 1tsp each of crushed garlic and grated fresh ginger. Add a drop of honey and top with toasted flaked almonds. Serve with 3 vegetable portions.

MORE: Simon Cowell drops half a stone after cutting THIS from his diet: ‘He has loads of energy’

Choose one mid-morning and one mid-afternoon (optional):

  • Small pot of houmous with raw vegetable sticks.
  • Small pot of natural yogurt with 1tsp honey
  • A rice cake topped with sugar-free peanut 
or almond butter

Fiona Kirk’s New 2 Weeks in the Fast Lane Diet is available from and Apple iBooks (£7.19 paperback, £4.99 eBook and £6.99 interactive eBook)

Words by: Emily Jefferies