That Sugar Film is a 2014 Australian documentary directed by and starring Damon Gameau. The film looks at hidden sugar in foods and the effect it can have on the human body.
The film follows Gameau's experiment on himself, changing from his normal diet containing no refined sugar to a 'health-conscious' diet low in fat but high in sugar, equivalent to 160 grams (40 tsp) of sugar per day. As a result, Gameau gained weight, grew lethargic, and developed fatty liver disease. The sugar diet was selected such that his calorie intake was not increased from his normal diet.