Why dieting doesn't usually work | Sandra Aamodt

Translator: Sara Vázquez Mera Reviewer: Serv. de Norm. Lingüística U. de Santiago de Compostela

Three and a half years ago,

Hai tres anos e medio,

I made one of the best decisions of my life.

tomei unha das mellores decisións da miña vida:

As my New Year's resolution,

como propósito para o novo ano,

I gave up dieting, stopped worrying about my weight,

deixei de facer dietas, de preocuparme polo meu peso

and learned to eat mindfully.

e aprendín a comer de maneira consciente.

Now I eat whenever I'm hungry,

Agora como cando teño fame,

and I've lost 10 pounds.

e perdín 4'5 kg.

This was me at age 13,

Esta son eu con 13 anos,

when I started my first diet.

cando comecei a miña primeira dieta.

I look at that picture now, and I think,

Cando vexo esa foto penso:

you did not need a diet,

"non precisabas poñerte a réxime,

you needed a fashion consult.

o que precisabas era aprender a vestir".

(Laughter)

(Risas)

But I thought I needed to lose weight,

Pero eu estaba convencida de que necesitaba perder peso

and when I gained it back,

e cando o recuperaba,

of course I blamed myself.

culpábame a min mesma, madía leva.

And for the next three decades,

E durante as tres décadas seguintes,

I was on and off various diets.

probei e probei distintos réximes.

No matter what I tried,

Daba igual o que fixese,

the weight I'd lost always came back.

despois de perder peso, volvía gañalo.

I'm sure many of you know the feeling.

Estou segura de que moitos de vós compartides ese sentimento.

As a neuroscientist,

Como neurocientífica

I wondered, why is this so hard?

preguntábame "por que é tan difícil?".

Obviously, how much you weigh depends on

Obviamente, o noso peso depende

how much you eat and how much energy you burn.

do que comemos e da enerxía que queimamos.

What most people don't realize

O que a maioría da xente non sabe

is that hunger and energy use

é que o cerebro controla

are controlled by the brain,

a fame e o consumo de enerxía,

mostly without your awareness.

sobre todo, de maneira inconsciente.

Your brain does a lot of its work behind the scenes,

O noso cerebro fai este traballo entre bastidores,

and that is a good thing,

e iso é unha boa noticia,

because your conscious mind --

xa que a nosa mente consciente

how do we put this politely? --

--como dicir isto de maneira educada?--

it's easily distracted.

distráese con facilidade.

It's good that you don't have to remember to breathe

Está ben o de non ter que acordarse de respirar

when you get caught up in a movie.

mentres estamos a ver unha película.

You don't forget how to walk

Ou o de non esquecernos de como camiñar

because you're thinking about what to have for dinner.

mentres pensamos no que imos cear.

Your brain also has its own sense

O noso cerebro ten o seu propio concepto

of what you should weigh,

do que debemos pesar,

no matter what you consciously believe.

sen importarlle o que opine o noso ser consciente.

This is called your set point,

A isto chámaselle "punto de partida",

but that's a misleading term,

pero é un termo enganoso,

because it's actually a range

xa que realmente comprende un rango

of about 10 or 15 pounds.

de entre 4,5 e 7 kg.

You can use lifestyle choices to move your weight

Podemos cambiar o noso estilo de vida

up and down within that range,

para subir ou baixar de peso dentro dese rango,

but it's much, much harder to stay outside of it.

pero é moitísimo máis difícil manterse fóra del.

The hypothalamus, the part of the brain

No hipotálamo, a parte do cerebro

that regulates body weight,

que regula a masa corporal,

there are more than a dozen chemical signals

hai máis dunha ducia de sinais químicos

in the brain that tell your body to gain weight,

que lle indican ao corpo que gañe peso,

more than another dozen that tell your body to lose it,

e máis doutra ducia que lle indican que o perda.

and the system works like a thermostat,

Este sistema funciona como un termóstato,

responding to signals from the body

responde aos sinais do corpo

by adjusting hunger, activity and metabolism,

con axustes nos niveis de fame, na actividade e no metabolismo,

to keep your weight stable as conditions change.

co fin de manter o noso peso estable mentres que as condicións cambian.

That's what a thermostat does, right?

Iso é o que fai un termóstato, non si?

It keeps the temperature in your house the same

Mantén a temperatura da casa

as the weather changes outside.

mentres que o tempo fóra cambia.

Now you can try to change the temperature

Podemos intentar cambiar a temperatura da casa

in your house by opening a window in the winter,

abrindo unha ventá no inverno,

but that's not going to change the setting on the thermostat,

pero iso non vai cambiar os axustes do termóstato,

which will respond by kicking on the furnace

co que a súa resposta será avivar a caldeira

to warm the place back up.

para que o espazo queza de novo.

Your brain works exactly the same way,

O noso cerebro funciona do mesmo xeito,

responding to weight loss by using powerful tools

responde ao enfraquecemento con ferramentas moi poderosas

to push your body back

que o forzan a recuperar o peso

to what it considers normal.

que considera normal.

If you lose a lot of weight,

Se perdemos moito peso,

your brain reacts as if you were starving,

o cerebro reaccionará como se estivésemos a morrer de fame,

and whether you started out fat or thin,

e tanto se eramos gordos como fracos,

your brain's response is exactly the same.

a resposta vai ser idéntica.

We would love to think that your brain could tell

Encantaríanos que o noso cerebro soubese

whether you need to lose weight or not,

se precisamos gañar peso ou non,

but it can't.

pero non o sabe.

If you do lose a lot of weight,

Se perdemos moito peso,

you become hungry,

teremos moita fame,

and your muscles burn less energy.

e os nosos músculos queimarán menos enerxía.

Dr. Rudy Leibel of Columbia University

O Dr. Rudy Leibel da Universidade de Columbia

has found that people who have lost

descubriu que as persoas que perderon

10 percent of their body weight

un 10% do seu peso corporal

burn 250 to 400 calories less

queimaban entre 250 e 400 calorías menos

because their metabolism is suppressed.

por teren o seu metabolismo suprimido.

That's a lot of food.

Iso é moita comida!

This means that a successful dieter

E implica que o que siga esa dieta

must eat this much less forever

debe comer iso de menos toda a vida

than someone of the same weight

en comparación con alguén do mesmo peso

who has always been thin.

que sempre foi delgado.

From an evolutionary perspective,

Dende unha perspectiva evolutiva,

your body's resistance to weight loss makes sense.

a resistencia do noso corpo a perder peso ten sentido.

When food was scarce, our ancestors' survival

Cando a comida era escasa, a supervivencia dos nosos antepasados

depended on conserving energy,

dependía da conservación da enerxía,

e mais da recuperación do peso tras a escaseza,

and regaining the weight when food was available

would have protected them against the next shortage.

xa o que os protexería nas vindeiras penurias.

Over the course of human history,

No transcurso da historia da humanidade,

starvation has been a much bigger problem

a falta de alimento foi un problema máis grave

than overeating.

que o abuso no seu consumo.

This may explain a very sad fact:

Isto pode explicar un feito moi triste:

Set points can go up,

os "puntos de partida" poden incrementar,

but they rarely go down.

pero case nunca decrecen.

Now, if your mother ever mentioned

Se a túa nai algunha vez menciona

that life is not fair,

que a vida non é xusta,

this is the kind of thing she was talking about.

esta é a clase de cousas ás que se refire.

(Laughter)

(Risas)

Successful dieting doesn't lower your set point.

Facer dieta de maneira correcta non vai diminuír o teu "punto de partida".

Even after you've kept the weight off

Incluso cando consegues manter teu peso

for as long as seven years,

durante 7 anos,

your brain keeps trying to make you gain it back.

o teu cerebro segue loitando para que o volvas recuperar.

If that weight loss had been due to a long famine,

Esta resposta sería axeitada

se a perda de peso se debese a unha longa época de fame.

that would be a sensible response.

In our modern world of drive-thru burgers,

No mundo actual, no que existen hamburguesas para levar,

it's not working out so well for many of us.

este sistema non funciona tan ben para moitos de nós.

That difference between our ancestral past

Esa diferenza entre o pasado no que viviron os nosos antepasados

and our abundant present

e o noso presente de abundancia

is the reason that Dr. Yoni Freedhoff

é a razón pola que o Dr. Yoni Freedhoff

of the University of Ottawa

da Universidade de Ottawa

querería levar algún dos seus pacientes

would like to take some of his patients back to a time

when food was less available,

a un pasado no que a comida era limitada,

and it's also the reason

e esa tamén é a razón

that changing the food environment

pola que cambiar a dispoñibilidade dos alimentos,

is really going to be the most effective solution

é a solución máis efectiva para combater a obesidade.

to obesity.

Sadly, a temporary weight gain

Por desgraza, unha ganancia temporal de peso

can become permanent.

pode converterse en permanente.

If you stay at a high weight for too long,

Se mantemos un peso elevado durante moito tempo,

probably a matter of years for most of us,

falo de anos para a maioría de nós,

your brain may decide that that's the new normal.

pode que o noso cerebro decida que ese é o peso normal.

Psychologists classify eaters into two groups,

Os psicólogos clasifican as persoas en dous grupos:

those who rely on their hunger

os que se fían da súa fame

and those who try to control their eating

e os que intentan controlar o que comen con forza de vontade,

through willpower, like most dieters.

como a maioría dos que seguen dietas.

Let's call them intuitive eaters and controlled eaters.

Referireime a eles como "comedores intuitivos" e "controlados".

The interesting thing is that intuitive eaters

O interesante dos "comedores intuitivos"

are less likely to be overweight,

é que teñen unha menor tendencia ao sobrepeso

and they spend less time thinking about food.

e pasan menos tempo pensando na comida.

Controlled eaters are more vulnerable

Os "comedores controlados" son máis vulnerables

to overeating in response to advertising,

a comer de máis motivados pola publicidade,

super-sizing, and the all-you-can-eat buffet.

piden as racións máis grandes e sucumben aos bufetes libres.

And a small indulgence,

Un pequeno capricho,

like eating one scoop of ice cream,

como comer unha soa cullerada de xeado,

is more likely to lead to a food binge

fai aos "comedores controlados"

máis propensos á farta de comida.

in controlled eaters.

Children are especially vulnerable

Os nenos son moito máis sensibles

a este ciclo de facer dieta e logo comer a fartar.

to this cycle of dieting and then binging.

Several long-term studies have shown

Numerosos estudos mostran

that girls who diet in their early teenage years

que as rapazas que fixeron dieta durante o comezo da adolescencia

are three times more likely to become overweight

teñen unha probabilidade 3 veces maior de padeceren sobrepeso

five years later,

cinco anos despois,

even if they started at a normal weight,

incluso cando partían dun peso normal,

and all of these studies found

e todos estes estudos atoparon

that the same factors

que os mesmos factores

that predicted weight gain

que predín a ganancia de peso

also predicted the development of eating disorders.

serven para predicir tamén trastornos alimentarios.

The other factor, by the way,

O outro factor, por certo,

those of you who are parents,

para aqueles que sodes pais,

was being teased by family members

son as burlas por parte dos membros da familia

about their weight.

sobre o seu peso.

So don't do that.

Así que non fagades iso.

(Laughter)

(Risas)

I left almost all my graphs at home,

Deixei na casa case todas as miñas gráficas,

but I couldn't resist throwing in just this one,

pero non me puiden resistir a traer esta,

because I'm a geek, and that's how I roll.

porque son unha "friki" e iso é o meu.

(Laughter)

(Risas)

This is a study that looked at the risk of death

Este é un estudo sobre o risco de morte

over a 14-year period

ao longo de 14 anos

based on four healthy habits:

baseado en catro hábitos saudables:

eating enough fruits and vegetables,

comer suficiente froita e verdura,

exercise three times a week,

facer exercicio tres veces á semana,

not smoking,

non fumar,

and drinking in moderation.

e beber con moderación.

Let's start by looking at the normal weight

Comecemos analizando os participantes

people in the study.

de peso normal.

The height of the bars is the risk of death,

A altura das barras indica o risco de morte,

and those zero, one, two, three, four numbers

e os números 0, 1, 2, 3 e 4

on the horizontal axis

no eixo horizontal

are the number of those healthy habits

representan a cantidade destes hábitos

that a given person had.

que presenta unha persoa dada.

And as you'd expect, the healthier the lifestyle,

Como podedes imaxinar, canto máis san é o estilo de vida,

the less likely people were to die during the study.

menor é a probabilidade de morte destes individuos durante o estudo.

Now let's look at what happens

Agora vexamos o que pasa

in overweight people.

coas persoas con sobrepeso.

The ones that had no healthy habits

As que non teñen hábitos saudables

had a higher risk of death.

teñen un maior risco de morte.

Adding just one healthy habit

Ao cambiar soamente un dos hábitos,

pulls overweight people back into the normal range.

as persoas con sobrepeso entrarían no rango normal.

For obese people with no healthy habits,

Para as persoas obesas sen hábitos saudables,

the risk is very high, seven times higher

o risco é moi alto, incluso 7 veces maior

than the healthiest groups in the study.

que o dos grupos máis sans do estudo.

But a healthy lifestyle helps obese people too.

Pero un estilo de vida saudable axúdalles tamén ás persoas obesas.

In fact, if you look only at the group

De feito, se atendemos soamente ao grupo

with all four healthy habits,

cos catro hábitos saudables,

you can see that weight makes very little difference.

vemos que o peso ten un efecto moi pequeno.

You can take control of your health

Podemos controlar a nosa saúde

by taking control of your lifestyle,

controlando o noso estilo de vida,

even If you can't lose weight

incluso sen sermos capaces de perder peso e mantelo.

and keep it off.

Diets don't have very much reliability.

As dietas son pouco fiables.

Five years after a diet,

Cinco anos despois dunha dieta,

most people have regained the weight.

a maioría da xente volve recuperar o peso.

Forty percent of them have gained even more.

O 40% deles incluso gañan máis.

If you think about this,

Se pensades nisto,

the typical outcome of dieting

o resultado habitual dunha dieta

is that you're more likely to gain weight

é ter maior facilidade para gañar peso

in the long run than to lose it.

que para perdelo.

If I've convinced you that dieting

Se xa vos convencín de que facer dieta

might be a problem,

pode ser un problema,

the next question is, what do you do about it?

a seguinte pregunta é: que se pode facer entón?

And my answer, in a word, is mindfulness.

E a miña resposta, en dúas palabras, é "pensamento consciente".

I'm not saying you need to learn to meditate

Non estou falando de aprender a meditar

or take up yoga.

ou a facer ioga.

I'm talking about mindful eating:

Falo de comer de maneira consciente:

learning to understand your body's signals

aprender a interpretar os sinais corporais,

so that you eat when you're hungry

e comer só cando temos fame

and stop when you're full,

e parar cando estamos cheos,

because a lot of weight gain boils down

porque moitas veces a ganancia de peso

to eating when you're not hungry.

débese a que comemos sen fame.

How do you do it?

Como podemos facelo?

Give yourself permission to eat

Permítete comer tanto como queiras,

as much as you want, and then work on figuring out

e logo trata de recoñecer

what makes your body feel good.

que fai que o teu corpo se sinta ben.

Sit down to regular meals without distractions.

Para as comidas principais senta a comer sen distraccións.

Think about how your body feels

Pensa en como se sente o teu corpo

when you start to eat and when you stop,

cando comezas a comer e cando rematas,

and let your hunger decide

e deixa que a túa fame decida

when you should be done.

cando debes facelo.

It took about a year for me to learn this,

A min levoume máis ou menos un ano aprender iso

but it's really been worth it.

pero merece moito a pena.

I am so much more relaxed around food

Estou moito máis cómoda en relación coa comida

than I have ever been in my life.

do que o estiven xamais na vida.

I often don't think about it.

Polo xeral, non penso nela.

I forget we have chocolate in the house.

Esquézome de que temos chocolate na casa.

It's like aliens have taken over my brain.

É como se os extraterrestres se fixesen co meu cerebro.

It's just completely different.

Completamente distinto.

I should say that

Debo dicir que

this approach to eating probably won't make you lose weight

este enfoque non che fará perder peso

unless you often eat when you're not hungry,

a non ser que esteas a comer sen fame,

but doctors don't know of any approach

pero os médicos non coñecen ningún outro enfoque

that makes significant weight loss in a lot of people,

que faga que moita xente perda peso de maneira significativa,

and that is why a lot of people are now focusing on

e ese é o motivo polo que actualmente moita xente se centra

preventing weight gain

en previr a ganancia de peso

instead of promoting weight loss.

en vez de en promover a súa perda.

Let's face it:

Sexamos sinceros:

If diets worked, we'd all be thin already.

se as dietas funcionasen, xa estaríamos todos fracos.

(Laughter)

(Risas)

Why do we keep doing the same thing

Por que seguimos facendo o mesmo

and expecting different results?

pero esperamos resultados distintos?

Diets may seem harmless,

As dietas poden parecer inofensivas,

but they actually do a lot of collateral damage.

pero en realidade, provocan danos colaterais.

At worst, they ruin lives:

O peor é que arruínan vidas:

Weight obsession leads to eating disorders,

a obsesión polo peso conduce a trastornos alimentarios

especially in young kids.

sobre todo nos máis novos.

In the U.S., we have 80 percent of 10-year-old girls

Nos EUA, o 80% das rapazas de 10 anos

say they've been on a diet.

din que fixeron dieta algunha vez.

Our daughters have learned to measure their worth

As nosas fillas aprenderon a medir a súa valía

by the wrong scale.

coa escala equivocada.

Even at its best,

Na mellor das hipóteses,

dieting is a waste of time and energy.

facer dieta é unha perda de tempo e de enerxía.

It takes willpower which you could be using

Malgasta unha forza de vontade que poderiamos utilizar

to help your kids with their homework

en axudar aos nosos fillos coas tarefas

or to finish that important work project,

ou en acabar ese proxecto tan importante,

and because willpower is limited,

e como a forza de vontade é limitada,

any strategy that relies on its consistent application

calquera estratexia que a precise

is pretty much guaranteed

é ben seguro

to eventually fail you

que vai fallar

when your attention moves on to something else.

en canto a túa atención se desvíe deica outra cousa.

Let me leave you with one last thought.

Déixovos cun último pensamento:

What if we told all those dieting girls

que pasaría se lles dixésemos a esas rapazas que fan dieta

that it's okay to eat when they're hungry?

que está ben comer cando teñen fame?

What if we taught them to work with their appetite

que tal se lles ensinamos a traballar o seu apetito

instead of fearing it?

en vez de a terlle medo?

I think most of them would be happier and healthier,

Supoño que a maioría delas serían máis felices e máis sas,

and as adults,

e como adultas,

many of them would probably be thinner.

moitas delas serían máis fracas.

I wish someone had told me that

Encantaríame que alguén me contase isto

back when I was 13.

canto eu tiña 13 anos.

Thanks.

Grazas.

(Aplausos)

(Applause)