I've never heard of it and had to do a web search. Now I have an inkling as to what it is about. Good luck with it anyway. And of course. it depends on the purpose you have in mind for dieting.

I have never followed any fad diet though occasionally, usually following tests at the doctor's, I have pulled myself into gear over indulging in unnecessary and un-nutritious foods. Many years ago I had bad arthritis and I read a very old book which convinced me to go cold turkey on all meat, sugar and tea. My pain increased for a while (detoxing) and eventually decreased, then disappeared. I found the cause to be tea, and have never drunk tea since. BINGO! No arthritis. I went back on meat and sugar.

Each person has to work out what suits them. Though I don't like the sound of restricting so many things that are part of my normal (I mean usual) healthy diet. I love grains, legumes, dairy products. Nothing like a big plate of brown rice which the appropriate healthy additives to make an easy meal, legumes go great in salads or hearty soups and Greek yoghurt is refreshing with or without added fresh fruit.

What they term "real foods" are good but are expensive for me. I try to grow as much of my vegies as possible but it's not always possible, especially since we've been away for a month and now we are experiencing a long heat wave.

Viva, why do you say "Everything that we eat has sugar added to it"? Doesn't that depend on your own choice.

My mom did this. Yeah, I would consider it a fad diet, though with the right mindset perhaps it could be useful. No amount of fad diets will help unless you're committed to changing your eating habits for the better, permanently. My mom used it in hopes that it would be a step in the right direction to helping her change her habits. She found that at the end of it, she didn't crave the sugars anymore, which is helpful in trying to create good eating habits. Some people do 3 or 4 of the 30 day challenge back to back.

Some time back I was working a very physically demanding, repetitive job. I developed arthritis in my shoulder. The vegan diet boasts of being a cure for arthritis so I gave it a shot. Sure enough, no more arthritis. After I left that job, I left the vegan diet. IMO it's not good for your overall long term health because it forbids so many types of beneficial foods. I was sure pleased with it for a season, though!

I tend to think a balanced diet is the way to go. I heavily restrict sweets and refined carbs but by no means forbid them. A piece of cake at a party or your child's birthday, or special treats for special feast days has its place among happy and healthy family life, imo, if you are otherwise healthy.

I was checking out brown mustard.  Most have sugar or corn syrup.  
I did find one without sugar.  

There are sugar in food items that never had sugar in the past.  

I'm not really for fad diets.  This only 30 days.  Yes, raising your own food is the best.  I can't wait for summer because we get good veggies. One friend is really generous and gives us veggies.  

Why don't you make your own? I am not a mustard eater, but decided to search for recipes. The first that came up all contained sugar, so I was starting to wonder if sugar is essential. But No... then I searched for sugarless mustard and came up with this:  http://paleoleap.com/homemade-paleo-condiments/#s4

The manufacturers put sugar in probably for two reasons:
1. sugar can be a preservative
2. people get hooked on sugar  and it means they come back for more. (yes it's a drug like any other)

A little sugar won't do much harm, eg if I am making my own tomato sauce for pasta, sometimes the tomatoes can taste a little too acid, so a teaspoon or 2 of sugar corrects that. But it is a tiny amount in the whole thing.