The second hit comes from fat accumulation.  When the liver is overloaded with glucose and fructose from a meal high in starches and sugars, they are converted to fats.  However, only 20% of glucose goes to the liver, compared to 99% of fructose, thus high sugar snacks including fruit juices plays a greater role a major role in the storage of fat in the liver and also glycation.  When the liver accumulates an extra 2 or 3 pounds of fat, it function of regulating blood sugar (glucose) is hindered.  Then insulin which also functions to lower blood glucose, must be secreted in a higher than normal level.  Insulin functions to cause the body to burn glucose and thus to stop burning fat and store it.  Thus higher than normal insulin is what causes the stead weight gain that results in obesity.  All this starts with the double whammy of glycation and fatty liver.  The NHANES study found that over 30% of adults have excess fat storage in the liver (non-alcoholic fatty liver disease, NAFLD), a serious medical condition that can progress to cirrohosis of the liver.  

It takes the combination of both fructose & glucose.  This explains why the Orientals on a traditional diet do not have a weight problem:  their diet is high in refined carbs (glucose) and is very low in sugar.  Those who deviate with added sugars get fat.  Fat also accumulates in the pancreas, and in excess reduces the production of insulin to cause type-2 diabetes (T2D).  Obesity and T2D are caused by diet and can be fixed by diet. 

The fix for the long-term over weight is to remain in the fat burning mode.  Since both proteins and glucose (carbs) cause insulin secretion, simply eating less will not keep the dieter in the fat burning mode.  Moreover, the hormone leptin secreted by fat (adipose) tissue will function to restore weight by reducing metabolism 25% or more, this will increases appetite by making the dieter desire food to feel better.  When we are sleeping the small store of glucose & glycogen is burnt, than the body switches to metabolizing stored fat.  By not eating when getting up, fat burning continues.  Fasting is the fix for the accumulated fat in the liver, pancreas, and adipose tissue.  The scientific literature is clear on this fix.  The most successful for those who are obese or have type-2 diabetes is alternate day fasting.  Less series cases can simply skip their breakfast, the short-term fast.  I have prepared a number of papers on what to eat, and fasting.  There are five recommended diets depending on the health situation at Cleansing Diet and what to eat, and much more at its long version.   Our metabolic system has evolved for short-term lack of food thus fasting is easy.   While sleeping the cells during fat metabolism undergo repair, one main system is autophagy.  Thus fasting and ketogenic diet (very low carbs) promote healing.  By extending the healing process, the risk for the diseases of the western diet are very significantly reduced.  This fact has resulted in my going a ketogenic diet at least one week a month, and to 6 out of 7 days a week skipping breakfast.  These two changes has resulted in a loss of 6 pounds, I am now as lean as when I graduated high school in 1962, and I have the energy for weight training, running once a week 2 miles, and swimming at least twice a week a half mile.  Cardiovascular fitness is strongly associated with avoiding age-related conditions.