“At 15, I was 9kg heavier than I should have been and didn’t know why, because my weight had been normal up that point,” says Nelson, who is in her early forties and lives in the state of Colorado.

She started dieting in her early twenties.

Thinking “a low-carb, high-fat, high-protein diet was the way to go”, she first followed the Atkins plan, which allowed her to keep eating a favourite food, bacon.

She could never stay on a diet for longer than a month; even if she lost a few kilos she would put them back on – and a few more.

When she tipped the scales at 88kg, and with 43 per cent body fat, Nelson had a serious talk with her doctor, who “highlighted all my health issues and told me that I needed to lose 18kg”.

Nelson believed that prediabetic or diabetic people should avoid carbohydrates and follow a high-fat, high-protein diet. “But I was so desperate for a solution that I bought the book and read it immediately.”

“Dr McDougall had been helping people lose weight for more than 40 years but I’d never heard of him before, and the information in his book was new to me,” she says.

Convinced that she needed to change how she ate, she questioned where she would find protein and calcium – a plant-based diet excludes meat and dairy products. But McDougall’s book addressed those concerns.

She learned you can still eat large amounts of food while losing weight by focusing on low-calorie dense foods that fill you up faster and keep you feeling full longer, such as fruit and vegetables – even potatoes.

A 100-gram serving of potatoes, say two-thirds of a cup, has about 80 calories; a 100-gram serving of minced beef has three times as many – about 250.

Nelson started her family on a low-fat, plant-based diet, keeping meals simple and familiar. Her husband was not keen, but agreed to support her and try the diet for a few months.

She developed “cleaned up” meat-free versions of their favourite foods: spaghetti with tomato sauce, baked potatoes, and burritos filled with rice, beans and salsa.

As the weeks progressed, she experimented with other ingredients and tried new recipes.

The diet change paid off. After the first week Nelson had lost almost 3kg, and after a month she was 9kg lighter. After 14 months, she had shed 32kg.

Seven years on, Nelson has maintained her physique, and her weight ranges between 53kg and 57kg.

The couple’s two children, now a teen and preteen, are healthy and thriving.

Nelson shares the benefits of the vegan lifestyle widely. She has published several cookbooks – and taken social media by storm.

Known as Plantiful Kiki, she has a YouTube channel with 247,000 followers; more than 184,000 follow her on Instagram, and 106,000 on Facebook.

These low-fat dishes use a variety of whole grains, vegetables, fruit, nuts, seeds, beans and lentils that deliver a nutritious and flavourful punch.

Her family loves the sauce over pasta, as a sandwich spread, and as a dip with baked tortilla chips.

Nelson shares her recipes in her inspiring cookbooks – Plantifully Wholesome, Plantiful Kids and Plantifully Lean. Plantifully Simple will be launched this July.

If you think plant-based equals plain and boring, here are some recipes titles from Nelson’s upcoming book:

• Raspberry Lemon Poppy Seed Pancakes;

• Chocolate Peanut Butter Oatmeal;

• Garden Vegetable Chickpea Omelet;

• Butternut Squash and Kale Salad with Cranberries and Pecans;

• Apple Pimento Grilled Cheese with Caramelised Onions and Arugula;

• Hawaiian Street Cart Tacos;

• Creamy Sriracha Dressing;

• Heavenly Banana Brownies; and

• Maple Pecan Pudding.

The books distil the knowledge she gained from her weight-loss journey to help the reader understand how plant-based eating benefits a body, and offer meal plans.

Nelson is grateful for having discovered this way of eating because it has changed her life and health for the better – and she is especially glad that she no longer has to limit her carb intake.

“I love that I can eat as much as I want at every meal without gaining weight, and I love knowing that what I eat is nourishing my body at the same time,” she says.