Having spotted "Go Ask Jack!" T-shirts many times over the last two decades, we thought it might be interesting to speak with the man whose name is emblazoned on many local chests.

So we headed over to the Vitamin Center, a few doors down from Ross off Capitola's curvaceous Clares street, and took a look around. We found a clean well-vite'd place, around 1,200 square feet in size, carrying over 3,300 items including just about every small health-inducing object except food. Shelves groan with vitamins, minerals, amino acids, herbs, homeopathics, digestive aids, weight control (for both gaining and losing), skin care products, books, candles and oddities.

And we learned that this is the third iteration of the Vitamin Center. It first opened at 1820 41st Ave. in the Fish Market (now a dry cleaner), then next door inside Kaleidoscope (where a pediatrician's office is now located) until 1990. Jack worked for the original owners until he bought the shop in 1991. Its 41st Avenue address is attributable to Clares Street not yet existing when it opened in its current location.

After a few minutes, Jack of T-shirt fame himself was free, and we asked him some questions.

METRO SANTA CRUZ: What do people come into the Vitamin Center looking for?

MACDONALD: Me, me, me! I mean, my logo is "Go Ask Jack," so most people come in looking for me to help them.

Productwise, energy, weight loss and exercise support are the top requests, with immune support being right up there during the winter months. Especially once school is back in session.

Has that changed since you first started operating the shop?

Except for the increased interest in exercise support, it's pretty much the same. We just have more to work with--and are able to tailor a supplement program to individual needs better--than before.

What developments have you seen in nutrition supplementation that you consider the most promising and helpful?

Cleaner products. Less garbage like artificial stuff, carnuba wax, shellac, dyes, etc. The "does not contain" list has grown way beyond sugar, artificial additives or preservatives; it now includes salt, wheat, corn, dairy, eggs and animal products. The beneficials we list are whether a product is organic, non-GMO, if suitable for vegetarians, etc. We can't list everything products don't contain, but we try to address the most common concerns.

And labels are now required to list everything a product does contain. No secrets. We have such better understanding these days of good and bad ingredients. Way too many people are taking supplements without looking at the labels.

What books or other information do you consider the most generally helpful?

The Constitution. It gives us the freedom to choose, although that freedom is constantly being attacked. After that, all books and publications offering information on the subject of health and well-being are worth reading. Each has some tidbit of help. It just takes a long time to sift through it all. And that's something I've been doing for many years, which is why customers prefer to "ask Jack" rather than take on the sometimes overwhelming task. I can narrow the search and point them toward good references.

How do you navigate between giving health advice and simply guiding people?

My only health advice is to get educated and be responsible for knowing what options you have. Often I speak with people who have gone to a doctor for a problem and took whatever drug, or other course of action was recommended, without ever asking how it works or what side effects might occur. Funny thing is, I get asked all the time when they are buying supplements, which statistically are much safer than drugs.

I even access a computer data base that gives positive and negative relations between drugs and supplements so people can be better informed as to what they should and should not do. In that respect, I guide people to all manner of resources, information and health-care practitioners that will give them similar support.

How do you choose among the tens of thousands of products available and decide which ones to offer?

Most people don't realize that almost all the products in the market place come from only a few raw material manufacturers. Any distinction in quality lies with the manufacturer of the finished products.

For example, if a manufacturer is making tablets of MSM (methylsulfonylmethane, a form of sulfur that complements the glucosamine sulfate many people take for arthritis), many of them will add excipients --binders, fillers and coatings.

Most manufacturers don't know this, but the nature of MSM itself is such that if production is done correctly, no excipients are needed. It is not necessary to use any excipients.

You seem to have a lot of bottles with white background and dark red printing, which looks a lot like a house brand. It is, isn't it?

Yes, it is. I began working years ago with a company very concerned about the quality of the products they produce; a moderate sized family and employee owned company that produces supplements they take and give to their family members as well.

Because of their integrity and concern for doing the best they can, they were one of the first to test every lot of raw materials for contaminants, test again after production, and furthermore, test finished products for label and formula accuracy.

I've gone to their plant in Oregon, put on a lab coat and hair net and made the MSM that I talked about a moment ago--starting with weighing out raw ingredients and following all the way through the process to putting a label on the finished bottle. It is pure MSM. No additives. No excipients. It was fun, but more importantly, it gave me a greater understanding of the products I sell and use.

This company has even have gone so far as to put our private label in biodegradable bottles, a first in the industry, and something I am very proud of.

What plans do you have for the future of the shop or business?

To just keep doing as good a job as I can. My customers have told me I can't retire, so I guess at some point you might find me propped up in the corner still answering questions when I'm 120. Shouldn't be too hard, since I enjoy what I do so much. I try to keep the idea that each customer should be treated as my favorite family member and don't recommend or sell anything to them I wouldn't give to my family. So my work is more like spending the day with an ever growing extended family. What more could one ask for in a career?

The Vitamin Center, at 1955 41st Ave. #B-6, Capitola, is open 10am-6pm Monday-Friday, and 10am-5pm Saturday. (831.462.4697; www.goaskjack.com)

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