It's not just about weight loss

I already see that eating a healthier diet is helping me lose weight, but weight loss in and of itself is not the ultimate goal - overall better health is.
Heart disease runs in my family, plus I'm still undergoing chemo once every two months for small B-cell lymphoma in my sinuses. Certain foods are linked to shrinking cancer cells and inhibiting cancer cells from forming or spreading. Certain foods are good for your heart as well. It's nice to lose weight, it's nicer to see total cholesterol numbers drop, though. There are plenty of healthy veggies out there, and I've found I like some more than others, but almost all can be cooked or served some way that makes them taste anywhere from decent to delicious. But if certain foods can stop lymphoma cells from spreading, you better believe I'll eat them. And to lessen the chances of having to go through intrathecal methotraxte again (that's a spinal tap where they withdraw spinal fluid and replace it with methotrexate), I'd go in the backyard and eat grass and dirt if it would help.
I don't think any diet regimen can guarantee it will prevent cancer, heart disease, or any other disease, but if changes in diet can help increase your odds, it's worth it, at least for me.
Here's a few things I've found -
Cruciferous vegetables are among the healthiest veggies out there for several reason. From livestrong.com - "Do not underestimate the power of having cruciferous vegetables as part of your diet. Cruciferous vegetables contain powerful antioxidants, which may decrease inflammation and reduce the risk of certain chronic diseases. They contain glucosinolates, crambene, indole-3-carbinol and isothiocyanates, which have been shown to decrease cancer risks." The most common cruciferous vegetables are broccoli, cauliflower, kale, brussel sprouts, cabbage, and a few others. I try to have a serving or two every day, raw, boiled, or steamed. And if you are on a wheat/sugar free diet, don't be afraid to put some butter on them if desired.
Avocados are extremely healthy. Once again from livestrong.com - "Getting the fat in your diet from omega-3s and avocados can help support your heart health and reduce your risk of cardiovascular disease..." In my area, Aldi occasionally has avocados for 49 cents.
Also very good but I won't list all the details right now - squash (all varieties including zucchini), tomatoes, carrots, cucumbers, onions, asparagus, sweet potatoes. I'm still adding more kinds of veggies to my diet so the list will grow with more research and taste test. 
And saute your vegetables in olive oil, not vegetable or corn oil. Again, Aldi has the best price on olive oil I've seen.
For more info run searches for "most nutritious vegetables," "cancer-fighting fruits and vegetables," etc.