Low triglycerides with normal or high cholesterol can be due to poor eating habits, hyperthyroidism, malabsorption syndromes (including Crohn’s and most likely cause in your case), as a side effect of certain drugs (like
nicotinic acid, clofibrate), etc. Yes, cancers to can lower the triglycerides and so can AIDS, chronic panceatitis, chronic liver disease, post radiation side effect and protein intolerance.