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Weight loss injections/treatments

Discuss weight-loss injections and treatments, including personal experiences. Mumsnet hasn't checked the qualifications of anyone posting here. You may wish to speak to a medical professional before starting any treatments.

Original poster

Underweight risks?

48 replies

BaggyClothes · 21/03/2025 13:29

Anyone know if there are any risks associated with being a little bit (few pounds) underweight?

I don't think I can afford to be on mj long term. My weight is tumbling off so I could probably get to being underweight (BMI 18 ish) by summer. I can probably afford mj maintenance for another couple of months after that.

Because it's likely a bit of weight will creep back when I stop mj, I thought if I can get to a little bit underweight, then when the weight does come back a bit, I can stay slim! and stay within the healthy weight range!

But does anyone know if there are risks associated with being a tiny bit underweight? (not something I've had to think about before! And I'm sure I've watched documentaries about how being a bit underweight and under eating calories by a bit, can prolong life?)

OP posts:
frillygillymilly · 21/03/2025 13:30

I thought slight overweight people lived longer?

frillygillymilly · 21/03/2025 13:31

eg BMI of 26.

Original poster
BaggyClothes · 21/03/2025 13:33

@frillygillymilly

I've heard that too! 🤷 Too much conflicting advice has got me a bit confused.

But I'm guessing neither BMI 18 nor BMI 26 can be that bad for us!?

OP posts:
wherearemypastnames · 21/03/2025 13:33

Being underweight is more risky than being overweight

the difference in “allowable” weight gain would only be a few pounds - small percentage . That won’t make the difference between being successful at maintaining or not.

WorriedRelative · 21/03/2025 13:36

An ethical pharmacy will not prescribe to you if you become underweight.

There are risks to being underweight. Muscle loss, loss of strength, reducing body fat can cause hormonal issues and stop periods or affect fertility. Much depends upon how you lose the weight, your body composition and how low you go.

The healthy weight bracket is large, if you get to the bottom half of the bracket you will be able to gain a bit and still be healthy and slim.

Original poster
BaggyClothes · 21/03/2025 13:39

There are risks to being underweight. Muscle loss, loss of strength, reducing body fat can cause hormonal issues and stop periods or affect fertility. Much depends upon how you lose the weight, your body composition and how low you go.

Do you think those risks apply if you are just a few pounds underweight? I've never been underweight in my life and to be honest, part of me wants to know what that feels like! Just for a few weeks before I inevitably settle back to somewhere in the middle of the healthy weight range..

(Is it bad to wonder what it's like to be underweight? Just for a few weeks? Is it just me that's curious? Probably is!)

OP posts:
Original poster
BaggyClothes · 21/03/2025 13:41

I guess my theory is I go right down to BMI 18 (about 51kg for me), then probably slowly over time add 10kg so become BMI 22/23 or so...

(Better than stop at BMI 22/23 then creep back up to 27?)

OP posts:
wherearemypastnames · 21/03/2025 13:43

If you creep up from bmi 18 to 22 the creep will continue

better to get to 21 and then adjust if it goes to 22 - a small adjustments- rather than letting things go for a longer time when the bad eating habits will be harder to shift

Finallydoingit24 · 21/03/2025 13:44

I’d be a bit concerned if you are having thoughts like this because it sounds a bit disordered. Why would you want to be underweight? Getting to a really low weight doesn’t affect whether you’re likely to regain weight after a diet. I would imagine that it’s hard to get down that low without some serious undereating as well. For me, the healthy range for my height spans three stone and me trying to get down to underweight is the difference between losing 3 stone and losing 6 stone which is a massive massive difference and I don’t want to think about how awful I’d look if I lost 6 stone.

PsychoHotSauce · 21/03/2025 13:45

I think you might be surprised how difficult it is to actually lose weight to the point of being underweight. The lighter you are, the fewer calories you need to function and you'd have to eat basically nothing for a sustained period to have enough of a deficit for it to happen.

According to my (very slim and short) DMs fitbit, on a sedentary day she only burns 800-900 calories. To lose 1lb she'd have to eat 400 calories a day for a week...

Add to that your body getting used to the injection and your new "food allowance" and by the time you get anywhere near there your weight loss will have significantly slowed down.

W0tnow · 21/03/2025 13:45

Forget about the weight for a moment. How much muscle have you lost? How tall are you?

ComfortingSounds · 21/03/2025 13:48

It's not good for you to be underweight, no. You'll be tired and cold all the time, you won't be able to think straight, you'll get sick more easily, you won't be able to get comfortable sitting anywhere, and more on top of that.

The best thing is to do some weights in the gym and eat healthily. You'll feel great for it, have loads of energy, your mind will be work optimally, and you get the satisfaction of knowing you're strong and capable.

LightCameraBitchSmile · 21/03/2025 13:49

How are going from 30+ to 18 in a few months?

DazzyRascale · 21/03/2025 13:52

BaggyClothes · 21/03/2025 13:39

There are risks to being underweight. Muscle loss, loss of strength, reducing body fat can cause hormonal issues and stop periods or affect fertility. Much depends upon how you lose the weight, your body composition and how low you go.

Do you think those risks apply if you are just a few pounds underweight? I've never been underweight in my life and to be honest, part of me wants to know what that feels like! Just for a few weeks before I inevitably settle back to somewhere in the middle of the healthy weight range..

(Is it bad to wonder what it's like to be underweight? Just for a few weeks? Is it just me that's curious? Probably is!)

Like PP have said, there’s some real warning signs here of disordered eating. What if you like being underweight so much you don’t feel able psychologically to put any weight back on?

LegoTherapy · 21/03/2025 13:55

Sounds like you shouldn’t be prescribed any more because your thoughts are disordered around weight.

Original poster
BaggyClothes · 21/03/2025 13:57

So you think it's that disordered? I'm not sure. I just am so scared of putting the weight back on and I can afford a few more months so made sense to me to drop low in case of creep back up! And I'm super curious what it's like to be underweight - does no-one else have that curiosity? I love seeing cat walk models! My whole.life I've hidden under baggy, unflattering t shirts! To actually be able to wear whatever I like, and it look actually nice, would feel great, no?

OP posts:
SilenceInside · 21/03/2025 14:03

"I love seeing cat walk models! My whole.life I've hidden under baggy, unflattering t shirts! To actually be able to wear whatever I like, and it look actually nice, would feel great"

Why do you need to be underweight to achieve this, @BaggyClothes ? You can easily achieve this at a healthy weight. Catwalk models are a very specific body type, long and lean, not possible for other body types to emulate safely. Not even safe for many of them to maintain that look either, as is very well known.

Finallydoingit24 · 21/03/2025 14:04

BaggyClothes · 21/03/2025 13:41

I guess my theory is I go right down to BMI 18 (about 51kg for me), then probably slowly over time add 10kg so become BMI 22/23 or so...

(Better than stop at BMI 22/23 then creep back up to 27?)

Why do you think it works this way - that you will inevitably gain 4 BMI points and then stop? It’s not how it works. If you start gaining when you are underweight then you won’t necessarily stop at BMI 22 and you might well have fucked your metabolism by starving yourself to get down to such a low weight.

And assuming you were BMI 30+ when starting, you are talking about shedding a huge amount of weight in a very short space of time - by summer.

I am afraid that yes you do sound very disordered around this. Do you also rely on high suppression to eat very low calories (I am guessing so if you think you will get down to BMI 18 by summer).

Finallydoingit24 · 21/03/2025 14:07

And I'm super curious what it's like to be underweight - does no-one else have that curiosity?

Err no, can’t say I have, sorry. I’m wanting to eat healthy to reach a healthy normal weight for my height. I don’t have a weird obsession with wanting to be so thin that it’s medically unhealthy and I’d be likely to lose my periods and grow excess body hair, no.

LegoTherapy · 21/03/2025 14:08

No, there is little attractive about the bordering on anorexic look. Bony is not a good look in my opinion but each to their own. Clothes won’t hang right, hair might start falling out, skin not looking as healthy, not as able to be as physically active as those with good muscle mass, feeling cold, more susceptible to infections, strain on vital organs.

PinkArt · 21/03/2025 14:08

You'd put all that effort in to work down from being obese, with all the associated health risks, to put your health at more risk by bypassing the large healthy range to get to the unhealthiness of being underweight? Yes it sounds very disordered.

MeridaBrave · 21/03/2025 14:12

My BMI is 26 and I’m at size 10 (but quite muscular). I can’t imagine what I would look like at a BMI of 18. The lowest I have ever been (before I gained the muscle) was 20, and I was really skinny then. I would be very worried that you have low muscle tone, which is problematic.

re: weight gain. Yes will gain 2kg water weight but if you eat too much will keep on gaining. You need to have a plan for coming off including a calorie limit. enough protein and resistance exercise.

Original poster
BaggyClothes · 21/03/2025 14:18

Thanks for giving my head a wobble everyone.

I will spend a bit of time thinking about what I'm thinking. I'm surprised no-one else has wondered what it's like to be underweight or wear clothes models wear! I didn't realize it was not normal to think this way - although in fairness my sample is just a few posters on this weight loss section of mumsnet! So hard to know what the average women thinks.

Ill do.some reflecting! Thanks for your thoughts!!

OP posts:
MightAsWellBeGretel · 21/03/2025 14:20

You need to tackle your disordered eating. Trying to be underweight is just ridiculous.

SilenceInside · 21/03/2025 14:22

But you don’t need to be underweight to wear what models wear. Of course people wonder what it’s like to wear clothes of your choice rather than baggy ones for covering up. I do it all the time. But I want to be a healthy weight and wear them. Not underweight.