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Weight management seems to be one of the biggest challenges in modern life. This is for sound and intuitive evolutionary reasons – we are wired up for an environment of food scarcity, programmed to eat whenever food is available, to keep eating as long as any is left, and to really go after the high-cal stuff. (Also, modern industrial society has learned how to hijack our pleasure centers. For one example, as given by St. Pinker, “We enjoy strawberry cheesecake, but not because we evolved a taste for it. We evolved circuits that gave us trickles of enjoyment from the sweet taste of ripe fruit, the creamy mouth feel of fats and oils from nuts and meat, and the coolness of fresh water. Cheesecake packs a sensual wallop unlike anything in the natural world because it is a brew of megadoses of agreeable stimuli which we concocted for the express purpose of pressing our pleasure buttons.”)

So the deck is pretty badly stacked against us. No wonder we struggle. And willpower is very limited here. Eating behaviour is controlled by our ancient lizard hindbrains – as are mating and fighting behaviour – and which our clever, newer, hominid forebrains have extremely limited power to override. I for one have wretched willpower, so I've basically had to figure out how to outclever myself, foodwise. But the good news is: when you stop eating crap fattening food, you really do tend to lose your taste for it over time. So effort is rewarded, and it does get easier. That said, research shows that people who lose weight and successfully keep it off have something in common: they think about addressing it all the time. Maybe it's not worth it to you. As we delightfully say in my homeland, "You pays your money and you takes your choice." Like I said, it ain't easy, but much of life isn't. However, there are a few easier wins, below. Incidentally…

You can't get weight management done on the exercise side. I'm sorry. There are a billion great reasons to exercise, daily and vigorously, but you can't outrun your eating. Look at it this way: your basal metabolic rate, the calories you burn sitting in a corner, is around 1,600. If you went out and ran a marathon every day, that only burns around 2,600. That's your entire theoretical range on the calorie-burning side: 1,600-4,200. You'll never burn more or less. On the consumption side, on the other hand, you can consume as few as 0 calories in a day – or if you sit around eating cheesecake, you could actually put away 25-30,000. In that enormous range of 0-30,000 is a lot more room to maneuver (for good or ill). And you can't outpace the cheesecake by going on 300-calorie-burning 10k runs; the run takes an hour and you can eat it back in a minute. My sense is that weight management is about 85% on the diet side.

Here's what I've learned about what works in weight management. (A propos of very little – except having had a couple of discussions around this recently, and wanting to share what I think I know with a particular friend.) I'm not providing very many citations, mostly because I can't be bothered, but it's mostly gleaned from years-long consumption of books, articles, blogs, and podcasts; and personal experience and experimentation. Your mileage may vary. You or your doctor might disagree. (There's shockingly little consensus in nutrition science.) I'm neither a doctor nor a nutrition scientist. It's worth stressing that weight management and health are not the same things – they overlap a lot, but not perfectly. (More on what to eat for health here and here.) All that said, I hope some of these tips are helpful.

• Cut out white sugar. It's a pure, rich, empty calorie source; and because your body metabolises it to glucose in no time, it rockets your blood sugar levels, leading to a quick insulin reaction, and a resulting blood sugar crash – making you hungry again all too soon. (Not to mention leading to insulin resistance, and thence to metabolic syndrome, known as "diabetes for beginners.") And so many processed foods have added sugar; just one of very many arguments against eating processed foods. (As St. Ferriss preaches, "There are 40,000 items in the average grocery store, and only a few of them won't make you fat.") Don't eat pure calories – cut out sugar.
• Switch to zero-calorie sweetener. If you've got a sweet-tooth like I do, you're in luck. You can now sweeten stuff with zero calories. I use pure sucralose powder. (It's the stuff in Splenda, but it's so sweet that Splenda is actually 99% maltodextrin. The sucralose powder, mainly, is enormously cheaper and more efficient; but Splenda is fine if you want to keep it simple.) Very many studies, and meta-studies, have shown zero negative health impacts of sucralose. That said, it's only been around about 15 years. If you're worried, or sensibly inclined toward the precautionary principle, use Stevia, which is herbal, all-natural, and has a many-decades-long history of use with no ill health effects (though the taste takes a little getting used to). Use it in anything you sweeten, like coffee – or smoothies!
• Cut out most other white foods – pasta, bread, rice, and potatoes. Metabolically, your body regards white bread basically like pure sugar. (Never mind that most American bread also has sugar added.) Very similar effect. All bleached-white grains are nutrient-free, blood-sugar-rocketing calorie-fests (and potatoes ain't much better). If you must eat grains…
• Switch to whole grains (bread, pasta, and rice). Because these don't have all the fiber-rich husk (and almost all of the nutrients) removed, your body takes longer to break them down and convert them to glucose, meaning it's slow-burning. The calories are the same, but they are absorbed over time and the blood-sugar spike is less. (Pro-tip: try whole-grain spelt pasta.) But, best of all…
• Cut out grains entirely. These weren't part of the human diet until the agricultural revolution 12,000 years ago, and arguably cause a lot of health problems. (Whole other dispatch.) But the whole point of them is that they are dense calorie sources that could support the dense populations of cities. That's the exact opposite of our problem now. (Pro-tip: quinoa is a seed (basically). But cous-cous is just finely-diced white pasta. Big difference. I wrote most of this in the BA Lounge at Gibraltar Airport. Got on the plane and they served up my special vegan meal – which turned out pretty much to be just a huge plate of cous-cous. I dug out the bits of vegetables and left the rest.) If you need to get some calories back in with grains taken out…
• Switch to beans and lentils. Legumes are beautiful. They're lower cal than grains, higher fiber, higher protein. Get keen on beans; there are many to explore. Lentils are even better.
• Really, seriously cut out things made out of both sugar and white flour. You know what I'm talking about: cakes, cookies, brownies, muffins. That stuff is crack. Just get it out of the house. (I have to get it out of the house, or I eat it in the middle of the night – virtually regardless of how bad an idea it is.)
• Consider going cold turkey on this stuff. No one suggests that addicts ought to try to moderate their heroin consumption. Sugary/starchy foods not only rocket your blood sugar levels, they actually produce serotonin. Carb addiction is real. (There's a fascinating theory that your gut bacteria have actually trained you to eat food they like. Also another dispatch.) I've found it's much easier just to cut this crap out all together. As soon as I have some, I want more – a lot more.
• Mainly – eat fruits and vegetables. Also pretty damned intuitive. Try to prejudice leafy green and cruciferous vegetables – broccoli, spinach, kale, cauliflower, Brussels sprouts. But any veggies are fantastic. Whatever you like. (Except potatoes. Which aren't a vegetable.) Super low-cal, high fiber, complex carbs, more protein that you probably realise (spinach is 44% protein, mushrooms 38%, etc.) and packed with nutrients. Some guys have come out against fruit for weight management, but I just can't get behind that. Yeah, it's got a lot of fructose, but that's a more complex sugar, and it's also packaged inside a ton of fiber and water, both of which slow absorption; not to mention that they're loaded with vitamins, minerals, antioxidants, flavenoids, carotenoids, phytochemicals, all very good things, and which most people don't get nearly enough of. Also at generally around 50 calories per 100 grams, it's massively less caloric than most of what most people eat. I'm pretty sure you can't gain any weight eating 50cal/100g food in a package loaded with fiber and water. Also it's delicious, perfect for your sweet tooth. Speaking of which…
• Think cost/benefit. Some things are worth a few calories. Others ain't. Can you think of anything nicer than fresh, sweet pineapple? 50cal/100g. Chocolate is 500cal/100g – minimum. Is chocolate nicer than pineapple? Maybe. Is it ten times nicer? No; it's not. For me, it's things like potato chips, or French fries. Are they nice? Yeah, a bit. Are they worth the massive hit of pure-carb calories? Not remotely. If you're going to have white bread, you know, make sure it's a freshly baked baguette in Montmartre or pizza in Trastevere – totally worth it.
• Quit or cut down drinking. You're not going to like this one, but alcohol is empty calories, and it's really easy to drink 1,000 calories before you've noticed it. (Which makes a pretty big difference in a 2,500-calorie day. In fact, I find it pretty easy to be in calorie deficit on any non-drinking day; but am virtually always in surplus on a drinking day.) On top of that, it's been demonstrated that we eat a lot more after drinking than otherwise. We also lose both judgement and willpower about food choices. When you do drink, consider switching from beer to cider. (As I recently did – it's about 2/3 the calories, healthier, and damned tasty. Just watch out for the sugar-laden processed ones.) Switch from sugary cocktails to vodka and slimline tonic; or Jack and Diet Coke, which is still delightfully sweet. Champagne is pretty good.
• Sugar-laden sodas are a non-starter (as I shouldn't even have to mention).
• Learn to use spices – they are your friends, because they make food taste good with zero calories. For that matter, it's amazing how much flavour comes out of things like onions and mushrooms when we apply a little heat and olive oil. Oh, yeah – I, as well as guys I read, say you should salt food to taste. There's little solid evidence that increased salt intake causes high blood pressure. There's actually a fair bit of evidence that it causes low blood pressure. The research is thin, based almost solely on observational studies (which one ought to know what those are worth). Anyone can look up this fact in five seconds. (For some reason, millions of physicians advising hundreds of millions of patients have declined to look it up.)
• Need a treat? Go smoothies! It's hard to beat sweet, frozen, and creamy. Blend up banana, berries of your choice (pear and nectarine are awesome, too), low-cal unsweetened almond milk (13 calories per 100ml!!!), and zero-calorie sweetener to taste. (Also optionally protein powder. I use soy, brown rice, and yellow pea – and only because I'm extremely active and thus constantly doing muscle repair. I don't think anyone needs protein supplementation to be healthy, or thin.) Then add a shed-load of ice and blend again. I've been drinking two pitchers of this stuff every day for over a decade, love it more every time, and wouldn't trade it. It tastes amazing, and you almost can't gain weight on it. (Like I said, I have no willpower, so I've had to find foods that I can consume an arbitrary amount of without doing damage. I told you there would be an easy win.) If you want to make it more decadent, here are some things you can add: milled flaxseed, (sugar-free) dark chocolate squares, cacao nibs (available at your health-nut store – chocolatey, and crunchy; awesome!), nuts (I think peanuts, pecans, and pistachios are nice), sunflower seeds, peanut butter (without sugar added!!!). (Bonus round: dark chocolate and peanut butter. Just – damn.) Obviously, the calorie load goes up this way. But a dark chocolate square or two goes a long way when flecked into a sweet, creamy, frozen, healthy, super-low-cal treat.
• Be careful eating out. You don't know what goes into stuff, so order judiciously. Also, ask to substitute any starches in your meal with salad or grilled vegetables. Leave the bread in the damned bread basket. Skip desert, go home, and make a smoothie.
• Cold is gold. Cold is a massively under-appreciated weight management tool. The human body, it turns out, is extremely efficient at doing work (hence the limited efficacy of exercise here) – but it's extremely inefficient at creating heat. There's more that could be said about the physiological basis for this, but suffice it to say your body has to burn a lot of fuel to keep your temperature in a safe range when the ambient temperature is a lot colder. Takeaway: going out to run in wintertime? Good for you. Don't layer up. Wear shorts and a t-shirt, and gloves if your hands get cold. Sure, it takes a little getting used to, but you learn to love it, not least since every second your body is literally bleeding calories (root of "calorie": calor, or heat) out into the air. (Every time I see guys running all bundled up, I despair at how they're knocking away the pile of diamonds to pluck out the one gold ingot.) Got a chance to swim in the cold sea? Awesome! Water is twelve times as thermoconductive as air (this is why being wet jacks hypothermia risk), so in this case the calories are actually being sucked out of you at high speed. (It's also been demonstrated in the lab that we can do more work, faster, longer, when heat is sunk effectively – i.e. cold helps us exercise.) Oh, yeah, and the whole time you're pouring frozen smoothies into the center of your body? Exactly.

Okay, that's most of what I've got, I think. Probably needless to point out, no one expects anyone to do all of this, all the time. These are just guidelines, or baselines, that seem to work – principles to follow, and areas in which one can make progress. Plenty of folks may disagree with plenty of it. Responses, additions, or rebuttals welcome in the comments.