In the late 1970's and early 1980's there was a huge movement to change the way Americans ate and this was because of the Framingham Study. In this study many end points were examined but mostly heart disease and cholesterol which had a direct relationship. LDL levels that were elevated were thought to have stemed from the diet. Due to this, Nutritionists and Cardiologists were encouraging low fat low cholesterol diets in children and adults. Also, there was a push to put high fructose corn syrup instead of cane sugar because of the expense of sugar or sucrose, and thus corn syrup appeared in everything. The body utilizes sugar and corn syrup very differently. In basic form sugar causes increase blood sugar and release of insulin and is metabolized by cells. Corn Syrup however which breaks down to fructose metabolizes in the liver and there it is converted into... you guessed it...fat! So a patient that consumes lots of high fructose corn syrup which is in everything can have elevated triglycerides and weight and then potentially heart disease. Today, The American Heart Association recommends women have no more than 6 teaspoons of added sugar/day. Men should have no more than 9 teaspoons daily.
So recently, in the 2000's there have been other changes to the recommendations and the theories surrounding heart disease. There is a component of heredity and knowledge about your family helps to determine your risk. The earlier family members have the disease the more risk for younger generation. Also there has been a change in diet to reflect lower sugar and carbohydrates. All carbohydrates are converted to sugar in the body. These are foods like rice bread and pasta. Eating complex carbohydrates like brown rice, whole wheat bread, other whole grains, and smaller amounts and more protein like fish meat eggs and cheese help with weight and lower insulin levels and glucose values. Omega 3/6 fatty acids have shown some promise to reduce inflammation and lower heart disease as well. Exercise is helpful to help utilize storred glucose and fat in the liver and lower weight. Knowlege of ones BMI is also helpful to manage weight and cardiac risk. Over 30 is classified as obese and over 25 is classified as overweight. Keeping it below 25 lowers risk for diabetes heart disease, sleep apnea, joint problems,depression,and also cancer.
Diet plays a large role in the risk and managment of many diseases and is always evolving. Sticking to a lower carbohydrate diet with protein from lean sources like fish and trimmed meat and good fats like olive oil, and other plant based oils help to keep ones heart healthy and other diseases away.