Two things I've been tracking lately (along with calories) is sugar and sodium consumption. The free My Fitness Pal app tracks calories easily and you can also select nutrition on the menu to view your intake of sodium, sugar, cholesterol and vitamins. I'm trying to drastically reduce sugar from my diet. Although I don't drink soft drink or add sugar to tea or coffee, it still creeps in.
The Case Against Sugar by Gary Taubes explains how our western society has become addicted to sugar and the unhealthy diet and disease that has resulted.
At one time the effects of sugar affected only the rich who could afford it. Elizabeth I is said to have black and rotted teeth something that the poor didn't suffer from as much. But when sugar became more affordable Western diseases resulted and in 1912 in America, during prohibition, sugar consumption increased when breweries were converted into candy factories. Even tobacco companies began marinading their cured leaves in a sugar sauce to make cigarettes more acidic and easier to inhale - reports of lung cancer shortly followed. (Alkaline leaves in cigars and pipe tobacco irritate the mucus membranes and stimulates coughing and were therefore not inhaled into the lungs)
Since then the battle has been fought between health advocates and the sugar industries. In 1930 The Sugar Institute was formed and advertised sugar as a health food to fight off colds and also a solution for mid-afternoon fatigue. The Food and Nutrition Board combated with omitting sugar on its list of recommended daily allowances for calories, protein and nutrition and declared sugar the worst of all foods.
On top of known sugar related diseases such as heart disease, diabetes and cancer, Alzeheimer's has been found to be associated with insulin, diabetes and sugar consumption.
In 2005 Scottish researchers reported that diabetic patients who took the Metformin drug (reduces insulin resistance) had a reduced risk of cancer compared with diabetics on other medications.
It's predicted that 30% of Americans will get diabetes mostly due, not to genetic disposition, but to overweight and obesity. Eugenia Calle published an analysis in The New England Journal of Medicine reporting that cancer mortality in the United States was clearly associated with obesity and those overweight were more likely (50-60%) to die from cancer than those with lean bodies.
One Scottish physician in a 1964 letter to The Lancet states "The refining of sugar may yet prove to have a greater tragedy for civilized man than the discovery of tobacco."