• Upgrades have been completed! Including conversations, 😁😎🏀⚾⚽ Emojis and more.. Read more

Orlistat questions- fat intake

S: 16st10.5lb C: 14st6lb G: 13st0lb BMI: 30.7 Loss: 2st4.5lb(13.86%)
Hi everyone, have been on Orlistat for just a few days now so doing a bit of research. I can't seem to find any information on optimum fat intake and am getting confused after reading dozens of threads on here!

My impression of orlistat is that it blocks 30% of however much fat is consumed when a pill is taken with a meal. By blocking the fat it blocks the proportionate amount of calories in that fat and thus reduces calorie intake. Combined with a reduced cal diet it basically boosts the weight loss. With me so far?

Now here is where I get confused. The leaflet says I should be having a 30% fat diet and spreading it out over the 3 meals. Snacks should ideally be low or no fat. It also says to have no more than 15g fat per meal. However I am struggling to eat anywhere near 30% fat or 45g fat per day unless I have naughty foods like chocolate and cheese! All the posts on here are describing you all eating really low fat foods that are 1-5% fat but if I only eat these then surely the orlistat has barely no fat to block anyway and is pointless? I know I will lose weight as I have 1400 cals a day and do exercise but I wanted these pills to give me a boost as I have 3 stone to lose.

Anyone got any pearls of wisdom to share? Plus how do you convert fat into calories to work out the %? And whats this 5g/100g rule.... not read that anywhere other than here.

Thanks in advance!

Get Rid of this ad and join in on the conversation for free today! Tap here!
Last edited:
hi jo, its confusing at first but you get the hang of it, the 5g fat for 100g rule is when u look at a packet for example snack a jacks, it will have a column thats the packet cals and fat but it will have a column for the 100g as well. just look at the 100g column for the fat. but for the cal look at the portion ur having i.e the packet.

i dont work out percentages i keep under 5g of fat for everything and ive been fine for the week.

also some days i only have 6g of fat a day sometimes its 30g just depends on what you eat but its really easy not to go over 45 :D
S: 332.5lb C: 313.5lb G: 196lb BMI: 49.1 Loss: 19lb(5.71%)
Hi and welcome, it can be quite confusing at times, but i think charlotte explained the 5g fat rule as good as i could!! Some days i only have 15 g of fat for the whole day sometimes more, but no matter how much or how little fats in your food the xenical will get rid of some of it!! I know it sounds strange but it really does work!!
S: 12st6lb C: 10st10lb G: 9st7lb Loss: 1st10lb(13.79%)
Hi Joanne, you have definately come to the right place for advice, the people on here are so supportive and have great advice. Best advice I was given was to join Free Calorie Counter, Diet & Exercise Journal | MyFitnessPal.com, I too was all confused about the fat intake but on fitnesspal you put in what you eat and it sorts it all out for you, what you should be having, what you have had etc and most days I don't get anywhere near my fat intake but kept going over on my protein but I am really getting the hang of it now, the chart and the girls on here have been invaluable. Good luck hun & welcome :eek:)
S: 16st10.5lb C: 14st6lb G: 13st0lb BMI: 30.7 Loss: 2st4.5lb(13.86%)
Thanks for the replies. I'm still unsure about eating only very low fat foods though given that the orlistat wont have much of a job to do and hence wont give much of a boost....? I kinda worked out that if I ate 30% fat and 30% of that fat was blocked then overall the orlistat would be lowering my calorie consumption by 9%. The less fat I eat the less calories are blocked.
true when you think like that but whats the point? if you keep eating the fatty foods and get slim once you stop the tablets you will pile on the weight. the whole idea for the tablets i think is to get your mind as well as your body into the routine of a low fat diet, if u make a mistake and eat fat then you get tangoed, its all to do with retraining you mind, its aversion therapy

by the way i didnt mean to sound harsh :S
Last edited:


Full Member
S: 12st11lb C: 11st12lb G: 9st0lb Loss: 0st13lb(7.26%)
i am totally with you joanne, the first week i was xenical for instance i lost 4 lb, and that was without calorie counting or stressing about fat intake, i was eating around 20g af fat a week, and who knows how many calories, week 2 and 3 i found myself counting calories and fat my fitness pal tells me i should eat 1200 calories, so 1200 calories and maybe 10g fat all day, have lost no weight in week 2 or 3, and its not looking good for week 4! saw my dr yesterday and he said xenical will only work in the presence of fat, so if i eat very little or no fat its not going to work, as it will only get rid of fat the body doesnt need or something like that. he said 1200 calories a day was way too low for a start i should be aiming for 1500 at least, as for fat the rule its 45g a day or less, but the lower the fat the less the pill will work. so i got from the drs meeting that if you are eating a very low low low fat diet you may as well not be taking the pills because theyre not doing anything. I have now given up counting calories and im just aiming to eat 45g or less of fat this week and see if that helps. having said that there are people on here losing weight eating a very low fat diet, but my dr argued that if you eat a very low fat diet you will lose weight anyway, so maybe we just have to find what works for us as individuals??......also the 5g/100 rule, i have found that i can go as far as 10/100 without side effects, and my dr had never heard of that rule, only that it was a guideline for low fat food, so for instance if it was more that 5g/100 its not that low in fat but it doesnt mean i cant eat it. so who knows???? good luck on your weight loss!!


Full Member
S: 12st11lb C: 11st12lb G: 9st0lb Loss: 0st13lb(7.26%)
Also he said the rda of fat was 70g so if you were to eat 45g and then taking zenical you are reducing the rda considerably, the body needs a certain amount of fat and calories to function. also i have spent the last few days looking at this realistically, i am only eating a very very low diet in case i get side effects, not because i dont want to eat "fatty foods", but "realistically" am i going to give up eating, cheese, margarine, buscuits, chocolate, etc etc etc for the rest of my life??? no, im just going to learn to eat them in moderation, because you can bet once i stop taking these pills and i know i wont get oily poo im going to eat them, so im going to swap very high fat foods for lower fat ones, and not give them up completely. on week 1 i was eating low fat cheese, low fat crisps, low fat choc (turkish delights) low fat margarine, etc etc etc, and i was actually enjoying my food, on week 2 when i read the 5/100g rule i had to cut out the above and more because you just cant buy any of it that is within the 5g rule, i found myself eating the same things over and over again, and it got me nowhere scales have not moved since 28th feb. confused, but determined to find an eating plan that works for me........
Last edited:


Silver Member
S: 18st5lb C: 14st2lb G: 10st0lb BMI: 35.1 Loss: 4st3lb(22.96%)
Hiya all,
What you have to think of is...by using xenical you are re-educating yourself on food...if you eat high fat foods then your going to store that fat....with xenical you can have 45g fat per day and under.....a low fat diet is essential as the food you are eating now s what will keep your weight off in the future, xenical isn't a magic pill to eradicate fat whilst you eat the wrong things !
Using xenical is about getting self control back and knowing what foods are good for us....if your not losing weight either your not eating as many calories as you think and your body is in starvation mode...so join my fitness pal and log all that you eat....exercise is important and it burns the fat......for every 1lb of fat it takes 3,500 calories to burn it.....so you need to burn as many calories a day as you can....
All of us are on low fat diets and we are all losing weight.....xenical works but it is the person that has to change....this is a lifestyle change not a fad diet......

I wish you all luck in getting to your goals we are all here to support :)
S: 16st10.5lb C: 14st6lb G: 13st0lb BMI: 30.7 Loss: 2st4.5lb(13.86%)
Thanks for the latest replies. I actually checked with my doctor and also have been on the Alli forum as it seemed to have more info on practical use of the drug (even though I'm on 120mg). Both agree that for xenical to boost your weight loss you do have to eat as close to 30% fat for it to work. Yes you need to count calories as at the end of the day thats what its helping with. I do also agree that eating healthy foods is best but there is no reason to not include good fats with that. People dieting seem to see fats as bad but they aren't all bad and are essential parts of the diet. Eating low low amounts of fat is pointless if you are taking Xenical/Orlistat and you would be better off without them really as they do cost the NHS a lot of money. I dont see them as a tool to prevent us wanting to eat high fat foods due to the side effects, thats not what they are for.

Stepped on scales this morning and have lost 4 lbs in 4 days. Had my first very treatment effects this morning too so its definitely working.


Silver Member
S: 18st5lb C: 14st2lb G: 10st0lb BMI: 35.1 Loss: 4st3lb(22.96%)
I still use olive oil in small quantities ...no side effects....I am trying kippers later don't know what that will do...lol
We know that all fat isn't bad but xenical you will suffer the consequences with if you have that fat....if you get the oily runny tango then you have overdone the fat....you aren't meant to go over the 5g rule and that is what the manufacturer has said!
We are on low fat diets and we are losing ...I was told by my Dr that you had to have a low fat diet and this trains you to what is right after you reach your target weight....if you read xenical website and their sister websites they say what foods to have and they are not high in fat.....
This is a lifestyle change not a diet .....that comes from my Dr......

Great news on your loss :)
S: 16st10.5lb C: 14st6lb G: 13st0lb BMI: 30.7 Loss: 2st4.5lb(13.86%)
Getting to grips with it all now and have found a happy balance on the amount of fat I'm having. Very mild treatment effects. Good news is that I've lost 6lbs in the first week. On the same diet without the pills I would normally lose 4lbs so am pleased with the extra boost. Thing is by the time I go back to the doctor in 3 weeks time my BMI will probably be just below 30 so he may not prescribe it again.
S: 332.5lb C: 313.5lb G: 196lb BMI: 49.1 Loss: 19lb(5.71%)
well done on the loss hun, thats great, if you dont get them again, you can always try the alli, which is a half dose, and apparently helps just as good, only thing is you have to pay for it, but you never know you might get it again!!

Similar threads