It is excessive calorie intake that results in weight gain, not sugar.
- Refined or any other sugar and other carbohydrates = 4 Cal/g
- Protein = 4 Cal/g
- Fat = 9 Cal/g
- Alcohol = 7 Cal/g
- Source: ucla.edu
Among free living people involving ad libitum diets, intake of free
sugars or sugar sweetened beverages is a determinant of body weight.
The change in body fatness that occurs with modifying intakes seems to
be mediated via changes in energy intakes, since isoenergetic exchange
of sugars with other carbohydrates was not associated with weight
change (BMJ, 2013).
There are epidemiological data, plausible mechanisms and clinical data
from diet intervention studies that provide strong support for a
direct causal/contributory role of sugar in the epidemics of metabolic
disease, and for an indirect causal/contributory role mediated by
sugar consumption promoting body weight and fat gain (Critical Reviews in Clinical Laboratory Sciences, 2016).
If sweetness tempts you to eat more than you want, it's a good tactic to avoid foods sweetened with sugar or other sweeteners. Stopping drinking sugar-sweetened beverages (soda, fruit juice...) can be a good start.