Researchers saw no difference until trials indicated they may not have the same effect in the human body. In smokers and people exposed to asbestos, synthetic beta-carotene may have caused an increased risk of lung cancer . Until more is known, smokers should avoid all beta-carotene supplements. Natural beta-carotene may have antioxidant activity that is different from the synthetic form.
Some doctors now recommend that people supplement only with natural beta-carotene.
Trials A study published in 1996 showed that beta-carotene supplements did not reduce heart disease in healthy volunteers. More information can be found on that in the next article. Extra beta-carotene may decrease sensitivity to light in some people. Evidence from lab studies suggests that beta-carotene is an antioxidant. Fat is required for absorption.