Positive caloric balance (defined as when caloric intake is greater than caloric output) especially in the setting of overweight or obesity is often associated with elevated triglycerides and low HDL-C (good cholesterol); LDL-C (that is the bad cholesterol) may not increase, but LDL particle number will usually be elevated resulting in increased risk of cardiovascular disease (heart attack and stroke).
During active weight loss in overweight individuals the good cholesterol (HDL-C) levels decrease. This is especially true for weight loss through dietary or drug therapy. However, after weight loss stabilizes, the HDL-C levels may return to baseline (original levels), and often increase above baseline. Intense or vigorous physical activity regime involving expenditure of between 700 kcal to 2000 kcal alone can cause significant increase in the good cholesterol (HDL-C) levels, and to a lesser extent reduction in the levels of the bad cholesterol (LDL-C).
During active weight loss in overweight individuals, LDL-C (the bad cholesterol) may initially become elevated before returning to baseline (pre-weight loss intervention levels), and then subsequently decrease. However, changes in LDL-C levels during active weight loss is determined by the nutritional method employed to lose weight. For instance, the use of high carbohydrate and low fat diet will result in increase triglyceride, decrease HDL-C (good cholesterol) and decrease LDL-C (bad cholesterol) levels during the weight loss process, whereas, the use of low carbohydrate and high fat diets will result in low triglycerides, but elevated HDL-C (good cholesterol), unchanged or increased LDC-C (bad cholesterol) levels.
In general, triglyceride levels tend to be affected by nutritional interventions, while LDL-C levels may not change with nutritional weight loss.
Surgical weight loss procedures that employ technique of bypassing the stomach achieve the most superior blood lipid levels.
How low should your bad cholesterol (LDL-C) go? Definitely the lower the more protective! Observational studies and randomized controlled studies have consistently shown that individuals with very low bad cholesterol (LDL-C) levels have significantly decreased risk of heart attack and stroke. However, individuals with low cholesterol levels have not been observed to have any known increased health risks from the low levels. LDL- C as low as 5mg/dl, have not been noted to be associated with cancer, liver disease or any other health problem, while on the other hand, it has been observed to be associated with longevity. The longer your LDL-C remains low the more protective!