That article cites no sources, and the FDA has retracted requiring warnings for products containing olestra
According to Wikipedia:
When removing the olestra warning label, the FDA cited a six-week P&G study of more than 3000 people showing the olestra-eating group experienced only a small increase in bowel movement frequency compared to the control group.The FDA concluded that “subjects eating olestra-containing chips were no more likely to report having had loose stools, abdominal cramps, or any other GI symptom compared to subjects eating an equivalent amount of [potato] chips”