Cult members act strangely. They may dress in last century’s fashions, use cult speak, or have unusual superstitions. Some of the ways they are atypical are shared by non-cultic members of minority religions, such as Judaism or Islam in the US; both such groups may abstain from culturally common food and drink, for example. But in cults, which can be ostensibly Jewish or Muslim or secular or anything else, these intentional differences from the surrounding culture are likely to be all encompassing.
Cult members are afraid of things the world accepts, and accepts things the world fears. I was born at home and raised without vaccines or medical care, even in cases of emergency. Those ideas scare much of my broader culture (and now me), but growing up I was proud to be set apart from the world, proud to have been born at home, proud to rely on prayer. Doctors scared us more than certain death.
Veganism and vegetarianism have become more generally popular in Western culture over the past decade, but before your average housewife was shopping for kale, many cults embraced the diet for a variety of reasons, both ecological and moral. Low protein diets are particularly favored by cults because they make members more compliant. (One can have a high protein veg diet, but not usually in a cult.)
Fasting, whether for piety or an eating disorder, can induce hallucinations. It makes people more emotionally vulnerable too, much in the same way as sleep deprivation. Rising early, waking many times a night for prayers, and performing difficult physical labor to the point of exhaustion are all forms of sleep deprivation common in cults. A fraught person lacks the tools to leave.
Cult members may follow a strict dress code or even wear a uniform. In group rules for modesty may be very rigid or very permissive; nudity is a broader cultural taboo some cults embrace and others reject. Cult members wear everything from robes to prairie dresses to their birthday suit. Whatever their position, it is likely to be off center from the standard.
I try to accept oddity, to make space for different ways of being. I do this in recognition of my own transition, from cult member to member of society. I have always been weird and I still am: I’m an atheist, and gay, and I still have some cult beliefs clinging on inside me. Other cult members and survivors are just as weird in their own way. They don’t need social pressures telling them there’s only one right way to dress or eat or speak or pray. They’ve had that. They need permission to figure things out for themselves.