I was a terribly picky eater when I was young. I still am, to some extent.
When we become parents, we all choose ways to be very unlike our own parents. One of my concious choices in this regard was to work dilligently to NOT raise another picky eater. My belief is that modelling positive attitudes towards food will go a long way to achieve that goal.
I am certainly no expert in the field, and there is a great difference between "picky eating" and "sensory processing disorders" where kids are unable to tolerate certain food textures. This is simpy what has worked for our family. Glean from it what you will, and feel free to respectfully disagree as well.
Here are my self-developed rules to that end:
1. Not every food choice is about taste
Don't pretend that every food you eat, or that you want your kid to eat, is delicious. Kids are smart and they will know you are lying to them or else think you're completely deranged. Brussel Sprouts are not my favorite food, for instance. I happen to think they're disgusting. But my husband and kid love them, so once in a while they choose them as our green vegetable. I eat them, noting out loud they are not my favorite but that each time I eat them I'm getting more accustomed to the taste and texture. I know they're high in sulforaphane, a powerful anti-cancer agent (just as broccoli is!) and experiencing the unpleasantness of consuming them is far outweighed by their nutritional advantages.
2. Never let food become a battle ground for control issues
No matter how you look at it, forcing somebody to eat what they don't want, is a matter of control. Encourage kids to try things by telling them "trying new things is part of growing up" and if they don't like it, remind them "maybe you'll like it more when you are more grown - we will try again sometime." Tastes change. I hated green beans when I was a kid and avoided them like the plague. As an adult, I ate them to be polite to my hosts and eventually began to enjoy them. Share stories like this with your kids. It has to be okay for them to not "like" something. When I was a kid, my father figure would become very frustrated about wasted food if we went to a restaurant and I didn't like what I ordered. This left with me a life-long aversion to trying new things, which I continue to overcome.
3. Encourage good choices
Explain to kids that whole grains and proteins provide you with lasting energy. On occasions when they are in a bad mood or cranky for seemingly no explanation, evaluate what they've eaten recently. One time our kiddo had a complete temper tantrum meltdown in first grade where she even pinched the teacher. Upon examining her food choices that day, we found out it was probably due to a sugar spike. It was "Donuts with Dad" day at school and her breakfast had consisted of one and a half filled chocolate donuts and "juice" which was not real juice at all. Even at 6 years old, she was able to understand that poor body-fuel choices lead to poor behavior choices at school, and has worked hard to avoid a breakfast full of treats since then.
4. Stock a variety of food
Have lots and lots of healthy choices around the house, but some treats are okay too. A cup of not-so-sugary cereal or a single poptart can be a wonderful treat if not eaten alone on an empty stomach. Our kid is welcome to have a serving of gummy worms if she first eats something like peanut butter & celery.
5. KISS - simple food is better food
I don't believe in becoming a short-order cook for your family, but I think it's okay to make some minor adjustments. Many kids will cringe at any kind of sauce on their food, or "weird green leaves" of spinach. I dn't have a problem cooking one fancy stuffed chicken or pork chop and fixing the rest rather plain. Fixing an extra of the "fancy" variety sometimes works as well, because it gives kids a choice to at least TRY it. Remember, they're not asking you to go to a lot of trouble cooking for them - they'd rather go through the drive through at McDonalds! Therefore, don't expect appreciation for some complicated meal that they probably will fear.
6. Help kids learn to read labels
Our first exercise in this was with yogurt. For a time, that was her favorite lunch-time protein. However, if you choose Yoplait Light, it has only 14 grams of sugar in it, whereas Yoplait Whip has a whopping 21! You can still have very yummy Key Lime Pie yogurt without the behavior effects of the sugar.
7. Educate about trans fats, food dyes, HFCS, and processed sugar
Start with trans fats. These are the "partially hydrogenated" oils that, when we consume them, stay in our arteries as cholesterol for almost ever! Anything that has any amount of trans fat is not allowed in our house. This eliminates a lot of my favorites, but more and more manufacturers are getting away from using them. Even a lot of fast food restaurants are banning them now. At McDonalds, you can't get beef without trans fats, but KFC no longer uses them. Dairy Queen uses them in EVERYTHING.
8. Calories in/Calories Out
It's an important part of nutrition and fitness education that we cannot escape. If we eat something high in calories, we will have to move more to burn those calories. Especially fat and sugar calories. I'm not saying have your kid count calories and keep a WW chart, but they should have general knowledge about it. As you are losing weight, include them on your journey and your philosophy of healthy living. They are our best watchdogs and cheerleaders.
And that's all I have to say about that.