First things first: I love my mom. She’s an incredibly sweet, caring woman and it is because of her nurturing I was able to develop an inquisitive, determined nature (as a kid, I was the human version of Curious George and no end of exasperation for my mother).

Like women all over the world, my mom checks with me in my role as the director of The Cosmetics Cop Team about some of her beauty concerns. Lately, it’s been about hair-care products. At age 63, like many women Mom is experiencing thinner, more fragile hair. Mom states that her hair is thinner, drier, and harder to manage than ever. She’s always on the lookout for new styling products, and often asks me about the Redken items her salon uses (I advise her to save her money and she typically doesn’t fall for the sales pitch).

Not too long ago, she became overly interested and excited about Kerastase, the ultra-expensive salon brand owned by L’Oreal. It didn’t help that her sister (who definitely has money to burn) raves about the products. My mom took her recommendations seriously because they have similar hair types. Eventually, she wrote to me asking for less expensive alternatives (I had a feeling the high cost of Kerastase would get to her). Her Kerastase phase seems to be over, and she’s been happy with some of the comparable products I recommended from another L’Oreal-owned company, Garnier Fructis.

Here’s where things went awry: Mom’s looking for a lightweight styling product to tame her hair and add shine but not weight. I recommended the Aveeno Nourish + Style Volumizing Foam. It’s a good, inexpensive liquid mousse that should work really well for her, as she heat-styles her hair. She thanked me and then proceeded to check out this product online. Several minutes later, another email from Mom landed in my Inbox:

“Honey, one person who reviewed this product said it left a residue. Now I’m not so sure about it.” I wrote back and asked why she zeroed in on the one negative comment (which we didn’t find to be true in our review for this product) and seemed to ignore the 20+ positive (I mean really positive) reviews also posted there. She didn’t have an answer but that one negative comment stood out like a sore thumb and her trepidation soared despite what I had told her. She was worried it would feel heavy on her hair, too.

I responded as follows: “Mom, I understand your concern, but you don’t know anything about that woman and why she wrote what she did. For example, what if this reviewer doesn’t wash her hair that often? What if she uses a hairspray that leaves a residue, or double processes her hair? What other products does she use? What is her definition of residue? What kind of hair does she have? Without more information there is no way to know why she liked or disliked a product.”

Of course, the sobering truth is Mom just didn’t believe me—at least not 100%. She’d rather believe an anonymous woman online than her own son, despite the fact I’ve been studying and writing about cosmetic products (including hair care) for over 10 years. I mentioned this exchange to Paula, and she could relate. She remarked that it was years before she could get her mother to stop shopping for skin care at Neiman Marcus in tandem with her friends who only wanted to believe expensive meant better (Paula’s mom didn’t break this habit until Paula created her own line PaulasChoice.com).

Sigh. It isn’t easy being a Cosmetic Cop. There are so many hurdles to overcome like obnoxious advertising and thousands of opinions from people without the research or expertise to evaluate or really understand what they are using. Personal experience means something, but given the wide, often fickle range of preferences and expectations, it’s not the most reliable way to assess a product’s value or efficacy.

But my own mother! That is just disheartening. I love you Mom (and, to be fair, I’m not the perfect son and, like everyone else, have my weaknesses) but sometimes I just want to pick up the phone after these email exchanges and yell saying, “Mom, just buy what I tell you, I am 1000% right. I have the science, research, and the largest comparison database of cosmetic products in the world I use to base my recommendations on!” Of course, if I did that she’d likely acquiesce and promise to listen better next time. But I know it’s only a matter of time before she sends me another question about a product a friend, co-worker, or her hairstylist mentions, and we’ll go around and around again.