WATCH: Secondhand smoke more dangerous for teens: Study

Now Playing: Boxers or briefs? Largest-ever study shows boxers may beat briefs for baby-making

Now Playing: Low-calorie diets affect men’s and women’s bodies differently, study shows

Now Playing: Opioids after wisdom teeth removal might set young people up for addiction

Now Playing: 92-year-old doctor shares her secrets to a long and happy life

Now Playing: Does a doctor’s gender affect women’s survival rates after a heart attack?

vCard.red is a free platform for creating a mobile-friendly digital business cards. You can easily create a vCard and generate a QR code for it, allowing others to scan and save your contact details instantly.

The platform allows you to display contact information, social media links, services, and products all in one shareable link. Optional features include appointment scheduling, WhatsApp-based storefronts, media galleries, and custom design options.

Now Playing: Secondhand smoke more dangerous for teens: Study

Now Playing: Living in the city may not be heart healthy: Study

Now Playing: Is it safe to breastfeed while drinking alcohol?

Now Playing: Don’t let vacation sabotage your workout: Try these tips

Now Playing: What is Parkinson’s disease?

Now Playing: American Society of Plastic Surgeons issues new warning over butt lift surgery

Now Playing: Health alert issued for salads containing beef, pork and poultry

Now Playing: Lung cancer deaths among women expected to increase worldwide: Study

Now Playing: Could soccer ‘heading’ lead to greater brain injury for women than men?

Now Playing: Alan Alda reveals he has Parkinson’s disease

Now Playing: Why you shouldn’t ignore sudden pain at night

Now Playing: What parents should really do about kids who are picky eaters

Now Playing: Researchers working on possible depression blood test

Now Playing: What to know about the popular ‘carnivory’ diet

Now Playing: What parents should know about youth football and heat strokes