Very high triglycerides can be caused by poor diet and not enough exercise. You may also have inherited very high triglycerides from a parent. Your doctor will tell you how to manage your triglycerides. If your weight is higher than what is considered healthy, losing even 5 pounds may help lower your triglycerides.
WORD likes it un-hyphenated but I don't. Long-term should be hyphenated but longtime should not be hyphenated, at least until a few more decades pass and the grammatical rules for the use of hyphens either relax or fade away. Here is part of an erudite commentary on this subject:
With compound adjectives formed from the adverb well and a participle (e.g. well-known), or from a phrase (e.g. up-to-date), you should use a hyphen when the compound comes before the noun: well-known brands of coffee.an up-to-date account. but not when the compound comes after the noun:tâs important to use hyphens in compound adjectives describing ages and lengths of time: leaving them out can make the meaning ambiguous. For example, 250-year-old trees clearly refers to trees that are 250 years old, while 250 year old trees could equally refer to 250 trees that are all one year old.