There are a lot of people who make dietary recommendations. It can be hard to figure out whom to believe.
There is a huge amount of money involved in food marketing, weight loss marketing and programs, and books about nutrition. According to ABC News, the U.S. weight-loss industry brings in about $20 billion of revenue annually. Another source claimed a worldwide market of a staggering $500 billion or more, for industries related to weight loss.
The issue of weight loss and food policy is a sensitive one, given the high prevalence of obesity as well as eating disorders in the modern world. These nutritional and metabolic problems are associated with strong feelings of depression and anxiety, negative thoughts and belief about self, guilt, shame, and frustration. Of course, there are life-threatening physical consequences of obesity as well as of other eating disorders such as anorexia.
There are now some good documentaries available describing the history and dynamics of the food industry, particularly the industries which supply sugar and corn syrup. For example, the films "Fed Up" (2014) or "Sugar Coated" (2015) introduce the viewer to troubling information about large corporations sweetening the world's diet, despite abundant evidence of dangers to health. The sugar industry has been compared to the tobacco industry, in the way that health concerns have been minimized or suppressed. A lot of commercial advertising and other marketing directly targets children from an early age; many children associate various sweet food products with play activities, friendly cartoon characters, free toys, etc. Some fast-food manufacturers sponsor health-related events or even resources for terminally ill children; while such charitable work is admirable, recent documentaries encourage us to consider it comparable to a cigarette manufacturer or a cocaine dealer sponsoring similar charities. If we associate these companies with such altruism, we may be more apt to feel good about consuming their products.
Ironically, sugar itself is a required component of human metabolism. Glucose is the main fuel for the brain.
Yet, the best way for the brain to obtain this glucose is from a diet low in sugar! Pure sugar or other simple carbohydrates in the diet cause a sudden surge in blood glucose, triggering a cascade of hormonal changes. Aside from the insulin response, there is a surge of pleasure from consuming sugar, which triggers an addictive behavioural sequence.
A habit of consuming sweetened foods leads to a reduction in the consumption of other nutrients. As one develops a habit of eating sweeter things, non-sweet food items are likely to taste more bland. It is hard for many people (especially starting off in childhood) to nurture a taste for vegetables when there are candies, ice cream, cake, cookies, or chips to choose instead.
As a component of improving mental and physical health, it is worthwhile to greatly reduce the amount of added sugar in the diet. This reduction would be satisfying, not only due to direct improvements in your health, but also because you would be shifting your financial support away from a massively wealthy and arguably corrupt food industrial complex, towards a more wholesome industry of local farmers.
Smaller intakes of sweets and simple carbs are likely to improve your appreciation of the esthetics of other food. Cutting sweets is not some kind of spartan sacrifice! It will lead to greater joy and hedonic pleasure in your meals! As you reduce sugar, your "addiction" to it will subside, allowing you to savour the tastes of all other foods, without the flavours being swamped by sweetness. If you do end up having an occasional sweet treat, you will be able to enjoy it more thoroughly, with a smaller amount of sugar needed in the recipe.