It usually involves cutting all added sugars, grains, sweet fruits and starchy veges. Low
carb is defined as less than 100g of carbs per day. Very low
carb is 25 - 50 g of carb per day. When you cut carbs you still energy so you get this from increasing your fat intake and making sure you have enough protein. Enough protein can be at least 100g for a woman and probably about 120g for a man. You can use a diet tracker to work out which foods have how much carbs, protein, and fats.