A Decades-Long Search for A Perfect Diet | Retro Report | The New York Times
Vložit
- čas přidán 11. 07. 2024
- Thirty-five years after the first dietary guidelines, how much do we really know about the science behind a healthy diet?
Grab the embed code for this video at Times Video:
nyti.ms/1J3fNYE
Produced by: RETRO REPORT
Read the story here: nyti.ms/1OKSAuU
Subscribe to the Times Video newsletter for free and get a handpicked selection of the best videos from The New York Times every week: bit.ly/timesvideonewsletter
Subscribe on CZcams: bit.ly/U8Ys7n
Watch more videos at: nytimes.com/video
---------------------------------------------------------------
Want more from The New York Times?
Twitter: / nytvideo
Instagram: / nytvideo
Facebook: / nytvideo
Google+: plus.google.com/+nytimes
Whether it's reporting on conflicts abroad and political divisions at home, or covering the latest style trends and scientific developments, New York Times video journalists provide a revealing and unforgettable view of the world. It's all the news that's fit to watch. On CZcams.
A Decades-Long Search for A Perfect Diet | Retro Report | The New York Times
/ thenewyorktimes
"what would jesus eat?"
that's the most american thing I've ever seen
It's more practical to ask What would Mr Rogers eat, as he is probably the only person in the modern era to make it into heaven... and he is a vegetarian for he didn't want to eat anything that may have had a mother.
Well he lived to be 33 so count me in
@@juanmanuelpenaloza9264 what about the female flowers from the plants he ate? Surely those count as mothers.
"Is America the land of the Heavy?"... I bursted out laughing LMAO!!
I like Michael Pollan's advice on eating healthy "Eat food. Not too much. Mostly plants"
How much is too much? What if I just eat oranges? Also, refined grains are plants themselves, but we know those aren't nutritious.
The "eat food" part is elaborated to be eat whole food: minimally processed, like steal cuts oats, or unproccesed, like fruit, vegetables, nuts, etc. The general census is to eat a variety of foods. The Okinawans (previously the longest living people) ate mainly a plant based diet with small quantity of pork or fish for celebrations. Traditionally, they ate until they felt "80%" full.
Hey, I have that book. Also, totally agree. Plants are very filling for something so low calorie. America needs to change its obsession with processed meat and fatty foods. And as for you, Aidan Davis, that just means that you should eat until your satisfied, not full. Also, if you eat too many oranges you could die from a vitamin overdose.
Aidan I don't know how serious your question is but here is the answer either way. One of the easiest ways is to only eat two meals a day as you would then not need to change your portion sizes. Then when you eat put your food on a standard size plate without stacking stuff on top of eachother. If you want to eat 3 times a day just use smaller plates. If you need a snack, dont eat sugary snacks (including sugary fruits).
As for the foods themselves dont make more than 1/4th of the meal meat and try not to eat excessive amounts of red meat or cold cuts (they are both proven carcinogens). Another 1/4th to a 1/3rd of your plate should be grains, try to make them whole grains but if not buy bread from the deli instead of the mass produced pre packaged loafs of bread (known carcinogen also). Try to fill the rest with mostly fruits and some vegetables, especially not those high in sugar. Eat or drink dairy but not in excess, so only a handful or two of cheese. Then try to drink only water and low sugar tea and coffee (but coffee has problems also).
So... practically speaking just eat less overall, consume much less sugar, eat less red meat, and eat less white bread and potatoes.
EXACTLY THANK YOU
Everything in moderation. Literally some of the oldest advice in the book...
Maybe diet isn't the sole cause. I live in a neighborhood with no sidewalks, without any businesses in walking distance. American suburbia was designed by the automobile industry to make people drive everywhere. Europeans don't eat low carb or low fat, but they're much skinnier. Maybe its because they walk more than we do.
Might be a factor but eating culture is way more important.
Everything is super sized in America. Free refills, giant servings and giant bags at the supermarket.
We have pavements everywhere in the UK and it is much easier to walk, and like everything else our portion sizes are smaller than the US, they help but we are only a little bit slimmer. This is not just a US problem.
People walk, ride bikes and use public transport in Europe
In Europe they tend to eat much higher quality food, the carbs they do eat are in freshly made bread and good food. I live in South Africa where majority of people don’t own a car and have to walk and take public transport to get anywhere and our obesity crisis is worse than in the us
this!!!! exactly right!
This is why I am studying nutrition and dietetics. There's so much information we have yet to know in this field that is constantly changing. We definitely have a long way to go.
Are people just refusing to watch the video before spouting their dietary beliefs in the comment section?
just don´t buy things that say "Captain´s" or "Mama´s" before the actual food and you´ll be fine
I think the biggest problem is that people want food to be simple, easy, quick, AND delicious. If you cut out fast food and processed foods, then you end up making things from scratch and it's no longer quick or easy... or so most think. It CAN be pretty easy, it's just that we're so accustomed to instant gratification that spending even just 20 minutes standing in the kitchen seems like a hassle... especially after 8+ hours at work plus commute time... not even getting started on kids if you have them. It sucks sometimes, but if you put in a little work you can find foods that you like that are dead-simple and healthy.
The next problem is that we don't realize how much what we eat today affects what we crave tomorrow and even the whole next week. If you're eating lots of sugar, fat and salt: food without it will taste bland. People say they "can't imagine" not having x, y or z. But the truth is: if you just tough it out for awhile, you re-acclimate to the natural flavors of foods. You get used to a new normal. For probably the first 20-ish years of my life (not counting when I was a baby) I think the amount of days I went without eating a single meat or dairy product was in the single digits. And so when I first started learning about the benefits of a "whole plant foods diet", I thought it would be impossible for me to give up animal foods. And for a few weeks it was pretty tough. But after that it became so easy I didn't even think about them any more for months and months. What we eat and what we crave is habitual. You get used to your diet when you stick with it long enough.
Here are the best principles I've found, for eating healthy, building muscle and losing inches:
1) Cut out sugar drinks completely (soda and juice)--after you do it for even a few days, you won't miss it at all.
2) Eat as little processed foods as you can get away with (that includes most foods purchased from any restaurant).
3) Try to never eat white bread (including buns), as these spike your sugar level.
4) Eat as many vegetables as you can. Eat plenty of fruit, too, but not too much.
5) Do cardio workouts (20-30 minutes), at least 5 days a week. Kettlebell is the BOMB!
6) Drink tons of water (helps burn inches and helps keep you feeling full).
7) Try to eat some form of protein with every meal, and use non-meat protein as much as you can (nuts, tofu, yogurt . . .)
8) Make lunch your biggest meal of the day; make dinner your smallest.
9) Fast as close to 12 hours as possible between your last food intake of the day and your first intake of the next day.
10) Get as much deep sleep as possible (stay off devices too close to bedtime, or use blue-blocking apps, as blue light interferes with deep sleep).
These principles work in harmony with one another, so that you start to get a virtuous cycle going.
Please note: You might actually gain weight (at least in the initial stages), because you'll be building muscle (which weighs more than fat), but you will lose inches and firm up.
I know your comment is years old, but just came to say your diet points are pretry much exactly how I've eaten my whole life. I cringe when I see coworkers and friends of mine complain about never being able to lose weight, and then minutes later gulp down a can of soda. Cutting out sugar does wonders, as do fruits and vegetables. Society as whole--at least here in America--used to be so much more fit compared to today, and it's obvious that the lack of processed foods back then played a major role
@@stee8345 Thanks for the endorsement! Stay well!
Qui est là grâce aux cours de Médecine en PASS ?
Mettez un pouce bleu pour savoir
nooooooooooon
Grenoble ici
@@moi7150 Moi aussi Grenoble
Came here to see all the non dietician experts 😂
Well excuse me but in many countries the goverment healthcare is heavily funded by private industries. :>
Here in Finland, even...
Man everyone knows dam well what they should eat too be healthy. All this crap is just looking for loopholes so people don't feel bad about eating the things they like. What's better candy or an apple? Coke or water. Fries or broccoli? It's actually beyond simple. People just don't want to do it
Those levels of decisions are fairly obvious to people, but when it comes to people making more precise decisions like athletes or people really trying to change it around quickly it becomes harder. Should I eat fruit or should I stick to a ketogenic diet? Can I have grains? How much? Should I go gluten free? Is a glass of red wine a day okay?
With all the marketing asking us to eat the bad foods, why would people not want to eat them? Not to mention the way burgers and fries are woven into American culture. And sometimes it's not simple - people think a loaf of white bread is better than fries, when it might be about equally bad if they are both processed.
1)Stop buying food that comes in a box or bag
2)Cook your own food using healthy ingredients
3)STOP drinking Sugar
Rice, potatoes, and other vegetables all come in boxes or bags.....
jballau How's obesity treating you?
Beckah Mataronas Obviously those are fine. I mean pre packaged/processed foods.
Panthers1521 go to the farmers market?
i completely agree with you. Don't even go in the grocery isles. No good happens there!!
I came here thinking I'd find an answer, but managed to get lost even more than I already was.
The answer: all are partly true. Eat less fat AND less sugar. More fruits and vegetables, more fiber, more water. Get more exercise, especially walking. More poultry and seafood, less fried or processed foods. Only eat when you're hungry.
Eat more veggies and excises everyday drink only water
The best advice.
I think the first place to start is overconsumption.
+Derek Shaw Except you never hear of anyone over-eating fresh fruit, vegetables, whole grains and legumes...
+audiovisuality Yes you do... you've never heard of people turning orange from carrots? High blood levels of vitamins are actually more harmful than helpful.
"It’s a medical condition known as carotenemia and, aside from the shock you’ll get from seeing your skin turn a cartoonish color, the condition is generally harmless."
dmodmodmo What about vitamin A, B, C, or D then? Excessive vitamin A can kill you. Most vitamins in high concentrations are harmful, it's just extremely rare to get to that point.
Beckah Mataronas True. Just check your facts
The one piece of advice I have gotten continually from not only my doctor but my mom is everything in moderation. it's not a bad thing to have everything that's on the food pyramid where bread and meat and vegetables and fruit are concerned sometimes those sweets can be tempting and it's okay to eat them every once in awhile but just simply don't Gorge yourself on the bad stuff.
I love it when I hear people talk about how they're going to focus on getting better research and studies. 😍
WHAT WOULD JESUS EAT?
Jesus would fast.
Veggies are supposed to be 1/3 of your plate, meat,fish, or meat with baked veggies; a quality carb like quinoa should be the last 3rd and you should drink a natural or close to natural juice +maybe some fruit. Also get enough sleep at night. I used to get very sick all winter every winter.
There's tons of people in my area getting sick with the flu, but so far I've only gotten sick once this winter a few days ago. I went ALL WINTER until Feb staying healthy. I got a killer sore throught that a feared was strep coming in, took 2 garlics and I was better the next day. I still could catch the flu, but I doubt it would be very bad if I did.
Then again I spend probably about $120 per week for just myself and my husband, so it's going to be very hard for a lot of people in this country to afford the kind of diet we have. The gov would rather spend money in vaccines rather then preventing these illnesses and giving you power over your diet. I'm not saying to ignore medical science, but if you can afford to do it try my diet.
Something else I do is I avoid soda all together, only eat sweets on the weekends, but not things that are sickeningly sweet. When I caught my sore throught it was because I bought sticky buns in Wal-Mart and didn't want to waste food even though they were choc full of sugar.
If your a pastry lover like me but strawberry danish or other fun but not over the top deserts, or eat your favorites in small quantities. Even just minimizing the sugar and switching to medium sugar teas/Arizonas I can garente that you'll feel much better
Less sugars would be a good start. Everything tastes sweet to me when I'm in the US
I lost over 120 pounds by eating clean. I still get my carbs but from veggies, fruits and roots. I only drink water and homemade juice ( only what I make in my house not the boxed juice full of sugar).
8:13 the rrrraw food diet
My partner, who's a nutritionist, says that you can't entirely cut processed food from a diet because it's not a realistic approach for people already suffering from obesity. Cutting the amount they eat is a better long-term measure once it is incorporated into a lifestyle.
"Processed food" is an unhelpfully vague term. I think it means pre-prepared food, which is likely to contain unhealthy amounts of sugar, salt, refined flour, hydrogenated fat, nitrites and nitrates, plus miscellaneous preservatives, colors and flavor enhancers.
I believe the microbiome and the effect of gut flora plus colon flora impacts human health to an extent that awareness of the issue has not be addressed toward the majority of American's. The same way the biological component of soil has been subverted by the focus on the chemical health of the soil. Physics, Biology, and Chemistry must be balanced in order for live to thrive at its' most efficient operating capacity.
You need help with apostrophes. Americans not American’s. Plural nouns do NOT have an apostrophe. Its’ is just plain moronic with the apostrophe AFTER the s. Look dude, it is becomes it’s. When some object belongs to the subject of a sentence you use its without the apostrophe.
I'm 37 years old and I just learned about calories last year. I started counting/restricting calories on February 20th 2017 when I weighed 206. Today is March 8th, 2018. I now weigh 135 lb. I've lost 70 lb in one year without any exercise simply by reducing calories. The school system failed me. They should teach us about calories every semester, every year, from the start. I should have learned how to control my weight as a child. Better late than never!
On a strict %100 placenta diet. It’s changing my life for the better. I can see noises and smell sounds. #nextlevel Get on it. HMU.
as an ex-anorexic, here's my advice: DON'T FOLLOW FOOD TRENDS!
AMEN
Anyone who says they know exactly what you should eat is a liar.
It is easy to feel overwhelmed and confused about what to eat and how much. My advice to anyone is to not look at CZcams comments for recommendations for pretty much anything.
I used to be overweight, I am not my ideal weight but I am now considered in a healthy range. If you want my advice it is to walk and exercise as much as you can. If there is a store nearby to you, make it a regular thing to walk there. You don't have to buy anything, the idea is to just have a purpose for your activity or exercise. And cut back on processed sugars in drinks/candy. If you drink soda for caffeine, use an alternative. I drink tea with no honey or sugar or anything added. It doesn't taste like soda, but it also doesn't have the sugar.
Best wishes to everyone.
I left a dislike on the state of the Union speech not because I didn't agree with the president, I actually agree with most of his stances, but because a news source disabled comments. Why would a news source not allow people to express their views and talk out their stances?
What's this about?
Its a shot at the Atkins Diet if im not mistaken
Fish, veggies, berries and nuts. Maybe some unprocessed meats. How does this perplex people?
I think just eating a balanced diet and not eating too much should do it.
lol eating healthy really isnt rocket science.
+Kraut and Tea still expensive for most
+SomPrince not expensive to buy grains, legumes and vegetables in bulk. You don't need superfoods to stay healthy
You can eat healthy enough to be at a healthy weight, but the problem is, what intake is good to keep your body alive longer? There's a lot of disagreement.
Kraut and Tea Nowadays yes since we have better studies
Actually we know a lot more about rocket science than we do about what foods are bad for us in the long term.
A Mediterranean diet is the best
Did you know.... ingesting protein also causes an insulin release? OMG!!!
Less than carbs and sugar. A sugar is considered a high spike in insulin after injesting it. Protein only increase slightly and reduced immidiatly after digested.
@@nickjohn2051 point?
@@AK-ic1yj You can eat protein and still maintain good blood glucose level. While eating carbs and sugar will spike the level until insulin became desensitize.
Im a type 2 diabetes, manage to reduce my blood glucose with protein diet.
Sugar is the demon here
The low fat/high carb diet push really screwed us all. We're fatter than ever, as a country. Media kills!
I'm surprised the danger of too much sugar isn't covered here.
After a family tragedy, i lived on Pepsi, beef jerky, candy, & exercise-i was addicted to it. At 5'3 inches, i dropped 40 lbs to my lifetime goal weight of 120lbs within 6 months.
One trend that is noticeable is we are talking about the United States here, land of fast and processed food. If we look at Mediterranean countries who have a diet that doesn't involve meat every day we notice a healthier longer life. I'm an American and I find it interesting the amount of soda/sugary drinks people consume and the food scarcity people have to adapt to with fast food, it's a difficult problem in our sugar addicted country thats for sure.
Low sugar, eat lean meat and healthy fats, incorporate a ton of fruits and some vegetables, keep processed food at a minimal.
Easy mode.
Epidemic of obesity and diabetes in America is your obsession with cheese and bacon and anything loaded with sugar
This guy gets it
Balance, variety and moderation. There is no perfect diet...just...moderation.
It's not a RepoReport if it doesn't start with that: 'TOOT - TOOT - TOOOOT'... Great infomentary!
It’s just having proper education on what’s good for you.
Everyone knows not to take the easy simple answer out. Anything good takes work.
When did your health not count for that.
Exercise is pretty important. Everyone's body is different.
There was absolutely no problem with the original guideline. Did people even read the full paragraph? It clearly stated "avoid too much fat, avoid too much sugar and eat a variety of food."
People just want to find an excuse to over-eat one thing or another.
Now you tell them to stop consuming too much sugar they will simply start swallowing as much fat as they can.
I stopped eating red meat, and now eat Captain crunch for dinner. Why am I so obese?!
Captain crunch contain tons of sugar.
STOP EATING PROCESSED FOODS!
There's no official definition for "processed" and some processed foods add no unhealthy ingredients. But yes, sausage, bacon etc. Limit.
SEDENTARY ACTIVITY plays a huge role in peoples diets and general health.
People spend around 8-14 hours a day sitting when humans evolved as creates that had to hunt and farm and move around for most of the day. The World Health Organisation ranks sedentary activity as the fourth biggest global killer and some studies suggesting that for every hour you sit, you lose two hours off your life expectancy.
It is appropriate that we have discussions and debate over diets although I think we need to start by establishing basic principles that can dramatically improve peoples health. This includes an adequate amount of movement (this can include simply standing up while you work) and exercise, as well as getting 8 hours sleep and being constantly hydrated.
I changed my lifestyle to include these 3 things even before I worked on my diet and I can now say that I definitely feel much more natural and have so much more energy.
You could also just eat what your body needs. People with these lifestyles eat "diets" of only world class athletes could withstand. It wouldn't hurt a lot of people to just simply eat less because you're body DOESN'T require as much as you're putting into it.
How to be healthy: Eat only when hungry, when you are hungry eat healthy whole foods, do not eat a lot of fat or sugar, stop eating when you are not hungry
It's no wonder that truth is stranger than fiction. Fiction has to make sense - Mark Twain
P/s: If anyone wants a lazy way to eat vegetables, but cabbages or long beans, etc. Rough chop it around 1cm thick or less if its not that size already. Then boil some water and pour them in the bowl of the stuff and let sit for like 5 minutes. Test the vegetable then remove all the water. When you find the right spot, makes it taste super fresh, yet not raw at all. Source: made a person who hated vegetables to enjoy my vegetable dish, trust me I know how to cook like a bachelor
de0509 also garlic salt and/or curry powder. They make every veggie taste immediately better
Nice video
Dear Americans, liking a certain food doesn't mean you have to eat it in every dish, multiple times. "I like meat and cheese, lemme wrap it in bacon and fry it in butter and then cover it in salt and powdered sugar" isn't a cuisine. Vegetables and legumes taste good without those things too.
So no one saw or was willing to speak out about tobacco?! Ike was a 4 pack a day smoker before his heart attack. Plus the meats we eat don’t eat good food, which makes them worse for our health. Maybe we stop factory farming food. Better food better health.
BBQ & Beer makes you happy!
No trans fat like in Denmark.
Combine white carbohydrates with vinegar like in traditional cooking fx sushi, potato salad, balsamic oil on toast.
To feel full; fiber, protein & liquid works best.
After having taken antibiotics or had bowel problems when feeling better eat something fermented.
Onze a month or onze a year go on a zero suger fast or a ketogenic diet or just a fast, let it last over 24 hours & probably less than a week
While the video was mostly focus on USA I'm wondering is there any evidence that our food diet has to be chosen by our geographical history?
+Наталья Дмитриева not sure... but americans should just exercise more, then they can eat anything, but that's not easy for the lazy
haggis is my primary source of oat bran....
I'm confused. it sounds like america is alone on that island. But just look at the diets of countries without a problem. I dont get why you have to swing from extreme to extreme
Eat vegetables, raw if possible. Change meat for fish. Avoid artificial foods. Try making your own sweets at home with olive oil instead of butter. Exercise or at least walk more
“Americans are fatter than ever before”
In a Tom Brokaw sounding voice by 80’s version Tom Brokaw himself 😂
Sources please? I'm but a poor health education student who needs to know more for an assignment
I think the Reaganomics have a part to play here.
How?
vegetables. meat. exercise. love.
Why not make more videos like this?
That's super weird for the government to have a panel of experts give dietary guidelines and then only adopt some of the guidelines to actually pass on to the populace. Why did you even ask them for advice at all?
I don't know why I think this is so funny
+Birdie Bowie Because you lack compassion
Birdie Bowie It's not their fault entirely, they were lied to by the government and "health authorities". If you have a little empathy and compassion it will actually bring more joy to your life.
well when you factor that 200 years ago many of our ancestors ate very different diets and as a result different ethnicities have different reactions to the same diet.
Look at where you come from in the world and eat what they eat there....think about it Americans come form every part of the world, and yet eat the same diet. Eat what your people eat, your body has adapted to that type of diet through generations.
and extreme example is how native eskimos eat super high fat and protein diets, very rarely have any sort of vegetables or fruits, and don't get and vitamin D from the sun because of the clothing they must wear.
So why don't they have vitamin D deficiencies? its because they eat the organ meat of large mammals. Their diet, culture, and knowledge passed down about that specific environment have allowed them to maintain a healthy diet.
Just eat real food that comes from nature.
Eat a bit of everything and exercise, it's done the trick for most people.
Fat was blamed and the sugar industry replaced the fat.
Fresh fruits and vegetables are Very inexpensive. Rice, oats, lentils, beans, are All inexpensive as well. Although most everyone knows and is well aware that processed fast foods aren't ideal, It's just that, the quick cheap ready made meals are readily available & super quick and convenient. Packing a healthy snack of nuts or fruit isn't as nearly desirable as a .99 McChicken or McDouble. Sad, but true.
no Mc at all. ronald mcd is the devil.
Name of soundtrack??
personne venu de l'UGA ? 💪💪💪 🔥🔥🥶🥶🥶🥶🥶🥶😹😹😹😹
What people need to do is eat a balanced diet of fruits, vegetables, meats, and grains each day. Having one or two unhealthy things is fine as long as it doesn’t become habit. Obviously unhealthy foods are oftentimes tastier and cheaper than healthier foods, but the cost of the hospital bills, medications, and time that you take to combat health issues if you eat unhealthy foods makes it more costly in the long run. Also, portion size is key. Don’t eat gigantic portions, even if it tastes good! You can always have food again. Like they said, one diet doesn’t fit all but if you eat things that aren’t manufactured for the most part and you exercise regularly, the pounds will eventually fall off. It takes time and patience but it will happen. I hope this is helpful to someone!
In my house, we eat meat, rice, veggies, and diary products in moderation ... and guess what? none of us is overweight :3
And it's issues like this that undermined scientific research in the Wester hemisphere.
No diet is perfect just don't eat too much and don't sit around all day
Eat in moderation. Eat mainly green and purple veggies and get plenty of fiber. That's it.
80-10-10 low-fat raw vegan diet. All natural foods. No manmade foods. Only organic low-fat fruits and tender greens such as lettuce and celery. It is the natural diet for humans.
Except for the no meat part?
It ain't rocket surgery: more whiskey, more cee-gars.
Wow
Just eat not too much.
#HighCarbGang
Still (?)
Low carbs, no sugar, intermittent fasting- problem solved
ok so what should we eat then?
sand
LOL
Kale, kombucha, chia seeds and spirulina.
Eat what you want--everyone dies eventually
Veggies, fat, meat, and fruits.
The one thing about food studies is there is always a new recommendation.
Lets take coffee. Within a 5 year period it would zig zag back and forward. Its ok to ok but hold on new study says other wise.
I can never take these food diet serious. Every 3 months we get told what not to eat and then a few months they same food should consider.
Leafy veggies and fish..
If a food has to brag about how healthy it is, it's probably not healthy
Americans think that fat is the worst. But the thing is that sugar makes you fatter than fat.
The problem more lies in how to eat healthy on a budget. We aren't a country of wealthy people. Sure, a simple, easy to make healthy meal of brown rice, some lightly sauteed or steamed veggies and a palm-sized piece of meat or tofu is doable, but if the cost of that meal is way too high for you to maintain... Then McDonald's it is. Solve the crisis of food cost and accessibility first.
Let's be honest... we eat things that taste good, I see nothing wrong with that.
eat food. mostly plants.not too much
wow 25 cents for a loaf of bread.
Muffy... sis... the carbs!
Has anyone thought to look to Asia and Europe.... they see totally fine and they eat everything
Chinese people are fine? In what planet do you live in???
Weight loss is just calories in Vs calories out. No one breaks the law of thermodynamics. If I burn 1500 calories a day and eat 1000 calories of doughnuts I'd still lose 1lb a week