Actually, it's just all about reducing calories. The average American adult eats roughly 2.8-3.2k calories a day. The recommended daily intake is a full thousand calories less than that. Effectively, if you cut down all of your portion sizes by a third, and manage to eliminate most sources of empty calories (processed sugars), you'll be on your way to a healthier lifestyle.
Surprisingly unhealthy foods:
Most fruit juice (they are actually fruit drinks on the packaging loaded with sugars)
Oils (it doesn't matter if its olive or sunflower, they can and will destroy your system - salad dressing is the biggest offender)
Processed Soup (just... no)
Non-citrine or melon fruits (apples, pears, and bananas are all effectively pure sugar)
Alcohol (it's directly processed into sugar, with beer being the single worst example - and no, light beer is virtually no better)
Oily, fatty meat (hamburger, fatty steak, most pork, hot dogs)
Desserts (a broad category, but acceptable IN MODERATION) I love lemon cake, but a slice or two a week is considered a healthy amount of sugar.
Beans in almost all forms
Oatmeal (plain oats, not anything prepackaged or pre-made. Quaker oats absolutely saturates their prepared products with sugars)
FISH (if any food can magically help you out immediately, switching from red meat to fish is the answer. It's basically a super-food.)
A managed diet of 2k calories will, by and large, keep you at your set weight while lesser amounts will reduce it. A good, systematic weight loss plan is one that doesn't require starvation (which shuts down your metabolism and actually helps you gain weight), is easy enough to maintain (doesn't cut nutritional corners), and allows a degree of flexibility (vices here and there).
It's hard. I'm 194' cm., which is about 6'4" in US terms. My average healthy weight is 180 (+/- 18 pounds). Throughout college and my medical residency, I crept up to 220 through lack of exercise and eating 'easy' food. Macaroni and cheese still has a special place in my heart. I'm now down to 184, and it's only there because I make a point to really look at what I'm eating. In restaurants, you want to avoid sauces like the plague, as well as anything with a lot of overall preparation. Fresh steamed fish with greens and a helping of mashed-potatoes is fine. The steak drizzled in a soft white cream sauce served over a bed of pasta is something you'll want to watch. In everyday life, the secret is cooking. Pre-made or 'instant' meals are absolutely terrible for you (a blanket statement, and if someone proves me wrong, it'll be a first). Just making your own food (even if it's just a brown bread sandwich stuffed with some meat, cheese, and lettuce) is a hugely beneficial change.
Nonetheless, losing weight doesn't make you look good - that's what exercise is for. A managed exercise routine of 20-30 minutes every other day is more than enough to get you healthy and physically toned. Just focus on cardiovascular exercises (running, jumping rope, most non-contact sports). A play-date with my niece on the playground, a pick-up football game (European version
), a jog on a really nice morning - it's all it really takes. Breaking the chain of being sedentary is really all you need to do to get your metabolism running, and once it cues in, weight loss becomes even easier.