"Portion sizes have been getting bigger through the years. Today’s 20-ounce soft drink is roughly double the size of the bottle of cola your parents might have had when they were your age. Those types of changes make it easy to ignore the serving size on the label and instead treat the whole package as one serving. (Have you ever put the cap back on a 20-ounce drink to save the rest for the next day?)"

Based on this paragraph, what can you conclude about the effect that bigger portion sizes have had on the amount that people eat and drink?