WATCH: Harvard professor calls coconut oil ‘pure poison’

Now Playing: The health benefits of coconut oil may be overblown, experts say

Now Playing: Dr. Jennifer Ashton reflects on giving up alcohol for a month

Now Playing: Customers pay 100 percent gratuity in #tipthebill challenge

Now Playing: Luis Fonsi rocks out to ‘Echama La Culpa’ live on ‘GMA’

Now Playing: Luis Fonsi performs his smash-hit ‘Despacito’ live on ‘GMA’

Now Playing: Catching up with Luis Fonsi live on ‘GMA’

Now Playing: What’s really in your Jamba Juice?

Now Playing: Cher releases her versions of Abba’s 1975 hits

Now Playing: Luis Fonsi performs his latest single ‘Calypso’ on ‘GMA’

Now Playing: Harvard professor calls coconut oil ‘pure poison’

Now Playing: We tried 3 clothing box services for kids for back-to-school season

Now Playing: Miss Denver’s Kayla Kline resigns in support of Miss America Cara Mund

Now Playing: Mom fights back after a neighbor calls cops over child walking dog alone

Now Playing: New video of Colorado murder suspect on relationship advice

Now Playing: Pennsylvania school hires armed officers following online threat

Now Playing: California congressman arraigned on charges for misuse of campaign funds

Now Playing: Tensions high after Trump slams Jeff Sessions

Now Playing: National Enquirer CEO granted immunity for information on Cohen

Now Playing: Hurricane Lane churns towards Hawaii

Now Playing: Meet 7 fierce female chefs setting a place at the table for women in the industry