The Metabolic Harms of Night Shifts and Irregular Meals

What shift workers can do to moderate the adverse effects of circadian rhythm disruption.

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We are winding down this series on chronobiology. Just two videos left in this series: Shedding Light on Shedding Weight ( ) and Why People Gain Weight in the Fall ( ).

If you missed any of the earlier ones, see:
• Is Breakfast the Most Important Meal for Weight Loss? ( )
• Is Skipping Breakfast Better for Weight Loss? ( )
• Chronobiology – How Circadian Rhythms Can Control Your Health and Weight ( )
• Eat More Calories in the Morning to Lose Weight ( )
• Breakfast Like a King, Lunch Like a Prince, Dinner Like a Pauper ( )
• Eat More Calories in the Morning Than the Evening ( )
• How Circadian Rhythms Affect Blood Sugar Levels ( )
• How to Sync Your Central Circadian Clock to Your Peripheral Clocks ( )

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Thanks for watching. I hope you’ll join in the evidence-based nutrition revolution!
-Michael Greger, MD FACLM

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Dave McKinnon

  • Food Guy says:

    Very interesting, it kind of always made sense to me that working during the night is so strange for the body’s for eating too! As the science explains the consequences directly. Thank you for all you do Dr. Greger, you inspire me everyday to be the best I can possibly be!

  • Dr. Vincent Esposito says:

    This is such a great topic, I recommend similar strategies for my clients and patients. Consistency is key. You are what you consistently do.

    Unfortunately, I’m not sure what the answer is to fix the night-shift worker issue. I live in NYC, so I am well aware of how many people quite literally make a living at night.

    Obviously, there would have to be some major changes at the state and federal levels, but the fact that there are so many night-shift workers nowadays (especially in cities), it could mean risking someone’s livelihood as well.

    I would love to know: what suggestions do you have as to how to help improve this system at the governmental level?

    • Joseph1NJ says:

      Government level? Ha! They’re still working on getting us safe water. Water! The government doesn’t serve us, we service it.

    • Angela’s Eye says:

      I totally see your point, but Dr. Greger/his team aren’t experts in policy change, they’re experts in nutrition and are here to give us the information in an easy to understand manner. I wouldn’t expect to get an answer from them on how to change the capitalistic structure of our society.

    • Dr. Vincent Esposito says:

      @Angela’s Eye Oh no I agree, I’m well aware they aren’t. I’m just saying this clearly affects millions of people, and each individual is not going to quit their job. I’m not looking for an answer to the question from them, I’m more asking you (the audience) if there are any ideas as to how it can be done at a greater scale.

    • Dr. Vincent Esposito says:

      @Joseph1NJ Unfortunately there’s a lot of truth to what you are saying. It’s really a shame

    • Angela’s Eye says:

      Vincent Esposito, MS, DC gotcha, yeah you’re right it’s definitely a huge issue and it’s really unfortunate that so many people have no choice but to risk their health just to make a living. 🙁

  • Chainsong says:

    i wonder how this would apply to people who move from say USA to China? obviously you eventually get over the jet lag and circadian rhythm seems to reset but what about our bodies and the way they handle food?

  • paulaqueiros says:

    Every time I watch these videos I realized I’m meant to be fat. I have chronic insomnia, I wake up at 7am but I only feel hungry at 10AM. I sleep much better after a heavier evening meal than with an early dinner.

    • Angela’s Eye says:

      Hey, im so sorry you feel like that but try not to be discouraged! your body must be used to that eating pattern if that’s what you’re typically doing, so of course you’re going to crave foods at those times. it’s not easy but you do have the power to change your habits, and over time it would become your new norm (if that’s what you want to do!). like I used to be a big night snacker and didn’t really eat breakfast til around 11 or 12, but then I learned from Dr. Greger that that’s not really ideal for health, so I started making myself eat in the morning, and getting enough food in during the day so that at night I wouldn’t be starving and need food. it wasn’t super easy at first, like sometimes id find myself wanting to snack at night even if I wasn’t really hungry, but once you build the habit it becomes easy/your new norm. If you want it, you got it. <3

  • Freedom Dividend News says:

    My parents were concerned about my weed habit. When I told them my night job was killing me, not weed, they stopped caring. It’s almost as if people don’t care if you die at the hands of a job

    • Ima says:

      My mom complained when i’m working during the day so i switched my schedule to work at night and she still complained. Now i just don’t tell her when i’m working.

    • NA says:

      They really don’t. It’s mostly the uneducated who are forced into working night/graveyard shifts, unless you work in healthcare.

    • Freedom Dividend News says:

      @NA I graduated college with two useless degrees which is why I was forced to work night jobs

    • Sky Building says:

      Freedom Dividend News ,,,,,i hope you are getting your marijuana through a store or at least someone who is not into other drugs too. My cousin died recently from ODing on some other drug. Be wise about the friends you hang with. Cocaine meth heroine and Lsd etc are no joke. There is a reason they called weed a gateway drug. It wasn’t the weed itself, it was simply the dealers often were mixed in other drugs and same with some friends – so higher likelihood of being offered the other drugs more often. ,,,,,,weed is good – i wish i had access to some when my father was dying so i couldve eased his pain. My cousin hung out with people who wanted to do other drugs though. I hope 🤞 you avoid those people ❤️

    • Freedom Dividend News says:

      @Sky Building I agree that some drugs are really bad like heroin, meth, & cocaine, but LSD is not a bad drug and helped Steve jobs make apple. I also agree that most people are bad influence

  • Jericosha says:

    I think a huge part of this is establishing healthy patterns. Going to bed early and waking early seems to be key and that’s REALLY hard for us in our world of cell phones and tv. We need discipline to be happy.

  • Angela’s Eye says:

    Thank you so much for this video series, it’s been so interesting and informative 🙂 I hope all of you who have to work night shifts are able to make a change if you see it possible. I am not speaking from experience so I dont know if this is doable, but maybe an idea could be to eat 2 meals — 1 right after your shift (in the morning), and one before it (in the evening)… that way you’re eating closer to the day time. You would have to adjust to fasting throughout your shift which could be hard, but it seems like that would be a bit better, rather than eating everything during the night. or even just having one snack during your shift if needed. I don’t know, just an idea. Or if you’re real wild you could be one of those mono-meal people, lol. I understand for lots of people it’s not financially possible to just “stop working night shifts” so I thought id offer an idea that could help. 🙂

  • Steve says:

    This really hits home. I’ve been working straight nights for almost 4 years now and have done shift work most of my working career. I’ve been Vegan for 10 years now but suffer from hypothyroidism and struggle with the weight. I’ve been trying to get to the gym but like you said there’s just no energy. In the morning after my shift I’m simply exhausted. In my line of work it’s very difficult to find a good paying day job….

    • Sky Building says:

      Maybe reevaluating all of your expenditures could help. Like, look around your home at all the things you own, and ask – “did i really need to buy this , or has it really helped me be happier?”. Look at all your subscriptions and (hope you’re not still paying for cable). Etc etc. Plenty of utube vids on this. Just reminding u that we often think we need more income than we actually need. It is amazing how much we (including me indeed) waste on luxuries and by failing to get the best deals on products we actually need.

    • Steve says:

      @Sky Building I’m already living with the bare minimum. I rent a room, have no debt. There’s nothing left to shave off. I’m a single income person and rent is very expensive where I live. I would consider a lower waged job but I can’t afford to lose too much of my income.

    • Andres Gonzales says:

      You work in the medicine field?

  • Psychophski says:

    Love this man. Total respect!

    • Liz Waters says:

      I do too! He’s changed my life. I’m completely PBD, and getting to Vegan as we speak. I’ve learned all the nutritional values of my foods and the correct vitamins to take.

  • Level Up Wellness says:

    This stuff is continually BLOWING MY MIND! This is so fascinating! I have reversed nearly all my arthritis symptoms on a plant based diet but always wondered why I feel just a bit tighter and less agile when I eat late at night. I can’t prove causation, but it sure seems like it could have an effect!

    Super interesting stuff! Love it 😄🙏🏼

  • Mrs. Bee says:

    Perfect timing!!!! I do both of these things and want to change the habits, thank you for the motivation to do so!!!!! 👍😉👍

  • Lisa Lightning says:

    We do the stay up late on the weekend thing and eat at two in the morning. Such a bad habit. I used to work at night at a restaurant but I was really young and resilient. I think if you work at night maybe the trick would be to bring a lot of fruit with you or something very light and easy to digest. Like a bunch of bananas.

  • S A says:

    I’ve been working nights and overnights for over 20 years. I’ve been mostly vegetarian for most of that time and vegan for over 5 years now. My sleep patterns and eating patterns have always been irregular but I’ve never had a problem with my weight. It’s been easiest on my body when I stick to sleeping during the day and staying up all night even if I have a day off. As I’ve gotten older I find it impossible to sleep more than 4 hours at a time but I’ve learned to nap and sleep in when I can. I’m sure it’s not as healthy for my heart but with proper eating habits I’ve managed to avoid weight gain in my 50’s. The tests simulate shift workers. I wonder how people like me would actually test.

  • Breanna Bryant says:

    I’m a nurse and worked night shift for almost 3 years. I was so sick and didn’t even know it until I went to day shift and got actual sunshine on a regular basis.

  • Danielia Bender says:

    So what are your suggestions for when to eat for people who work overnights and their schedule will not be changing any time soon?

  • 1RepMex says:

    Well i been working graveyard shifts for about 7-8 years and i feel perfectly normal. I do eat a plant based diet and i engage in lots of resistance exercise. maybe thay offsets it but idk. In your defense though im nowhere near as lean as i want to be haha. Good video btw! Very informative

  • Mariano Montiel says:

    Would love to see interesting studies on the science of sport nutrition! Hope they come out eventually!

  • 🦋Carolyn🦋 says:

    So hard to have a regular eating schedule when you work 11pm to 07:00 am, m-F as a security guard.My first meal I have at work,a few hours after I get there …but no matter what I eat”Always plant based &vegan”,I feel bloated after and miserable.Maybe like Dr Gregor says,eating at night is not good for your body truly.🤦I love my night job though.Eating habits maybe I have to change.

  • Rachel Goodkind says:

    Thanks for the info. I have never worked a night shift but know humans who have, it really messed up their lives. They were
    very happy when they went to a day shift, but it took them three months to get used to it again. I am a night eater, but feel and sleep much better when I have an early dinner.

  • Leticia Barraza says:

    Ojalá hubiera visto este video hace tres años…los cuales trabaje de noche…solo hacia una comida al día bastante cuantiosa y aún así subí 10 kilos…empecé a desorientarme y a tener insomnio y ataques de pánico…aunque ya trabajo de dia aún tengo secuelas pero todo va mejorando

    • Maria LC says:

      Yo trabajo 12 horas de noche una semana, de dia y otra de noche, ya llevo asi 2 años y medio… es de locos, tengo insomnio, cuando ando de dia no puedo dormir y a la 1 o 2 am. Me levanto a comer algo… trabajo 12 dias seguidos… y descanso 2. No he subido de peso. Pero con el insomnio tengo 😔😔😔

    • Domingo Esequiel says:

      yo maneje 28 años camion de carga a la hora que se presentara el trabajo hoy tengo 46 años y deje de fumar 2 que 3 droguillas el cafe y aun no se me quita el sueño quede tocado 😂😂😂😂😂😂😂

    • 144 1 says:

      A mi me pasó lo mismo hace un par de años,la secuela es que no como ni almuerzo a mis horas y me mal pasó y a veces me tiene que obligar a comer

    • Miguel Galindo says:

      Pues que poco aguante tienen,yo Boy para 30 años con turnos rolados muchas veces trabajando de noche 😾

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