'I felt weak': Duncan Garner reveals struggles after starting vegan diet

The AM Show host Duncan Garner says he's stuck to his guns commencing his vegan diet but admits it's been "tricky".

In July, Garner promised he would turn vegan if Labour polled high enough to govern alone. The party won in a landslide at last Saturday's election picking up 64 seats - three more than needed to govern alone.

Last Tuesday, Garner said he would stick to his word and a week later, he reasserted his commitment to the diet.

"Hand on my heart; swear on my kids' lives I have stuck to this diet," he told co-hosts Mark Richardson and Amanda Gillies on Tuesday.

But Garner also revealed the struggles he'd had with the diet.

"It's a tricky diet, I'll be honest," he said. "I felt weak a couple of times at the weekend."

Richardson told Garner he should "just fail" on purpose.

"You haven't said you feel good at - you said you just feel hungry."

New York Montefiore Medical Center Cardiac Wellness Program founder Robert Ostfield said fatigue on a plant-based diet is often associated with not eating enough.

"Although a plant-based diet is incredibly nutrient-dense, it is not calorically dense, particularly if someone is consuming primarily fruits and vegetables," he wrote for UK site Plant Based News.

"So it is quite possible that people who have transitioned to a plant-based diet may not be meeting their caloric needs, and hence feel fatigued.

"If you experience fatigue while on a plant-based diet, you can eat a higher volume of food and/or more calorically dense foods like nuts, seeds, whole grains, lentils, and/or avocados."

Last week, Garner revealed to Gillies he had been passing more gas than usual - something experts say is healthy and normal due to the amount of fibre consumed in a vegan diet.