Why does my weight go down, but fat percent go up?

[worengo]

I'm a little confused with the FitBit weight tracking. I have the Aria scale that syncs with the FitBit. I have lost 3.7 pounds since getting the FitBit, but my fat % has gone from 29.3% to 33% in that same timeframe. I am in the goal range of Calories In vs Calories Out on a daily basis mostly. I work out at least 30-40 minutes daily and pay close attention to what I eat.

Can anyone give me some insight as to why this may be happening? 

[Clrich53]

Thanks!

Sent from my iPhone

[Vanner46]

Thanks for the information on body fat measurement. It has certainly clarified this issue for me.

Regards, Jack.

[Vanner46]

Once again thanks for the info on body fat.

However; may I ask if the knee implants I mentioned previously have any effect at all on the readings?

[NikkiNakiNu]

Hey my weight is going down and I had a body scan saying my bf% has gone up. It's quite concerning really. I've lost lean body mass as well but not really enough to clarify the weight loss. I don't like my composition data at all so I'm no longer doing keto. Clearly I'm storing way to much fat most likely from over eating. My visceral fat is now high.  I'm going to go low carb and up my protein this has always given me better body composition. So clearly keto is not for me and yes I followed it properly for 2 months. I lost the same amount I would have if I was on low carb high protein but got **ahem** body composition results

[Dominique]

@NikkiNakiNu: what method/device was used for your body scan? It’s quite unlikely you have gained fat if you lost weight. How about body measurements, e.g. waist circumference? Keto is just an extreme form of low carb, so there’s not a big difference between "keto" and "low carb high protein". In the end, it’s about total calories (for weight loss). Keto works by keeping you satiated from the very high fat content. Protein also tends to be satiating, so upping your protein intake can have the same effect. Two months is a relatively short period to assess changes in body composition: you can’t gain/lose that much lean mass in a mere two months.

[Dominique]

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@Vanner46 wrote:

may I ask if the knee implants I mentioned previously have any effect at all on the readings?

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That’s an interesting question! Did you get your implants while you were already using your scale? If not, it would be a question to ask someone who did. I’d imagine the artificial materials in the implants would affect impedance readings from the scale, especially for knee implants.

[Soaptrail]

So how does Fitbit know when to start reducing my body fat % if I only use their scale while losing weight?  Do they guess?

[Dominique]

Fitbit (app / account) neither "knows" nor guesses anything about your body fat %. It just stores whatever estimate comes from a compatible scale or is manually entered by you.

A Fitbit scale (or any similar scale from another manufacturer) estimates your body fat % using bioelectrical impedance analysis. Usually, the body fat % estimate goes down when you lose weight, and vice-versa. However, "estimate" cannot be stressed enough, the number isn’t necessarily/always accurate.

[Vanner46]

Thanks. I will leave this topic now.

[ddk17603]

Fatty foods and carbs are not the problem if you know which ones to eat. You did not actually gain 7% of body fat in 3 days. If you weighed 100 pounds, you would have to consume an extra 24,500 calories. 

[rustyadams_99]

Sorry but I'm not buying this. Ive lost 40 lbs and my % body fat went from 20% to 32%. Fitbit is not measuring body fat, and the algorithm being used is not correct. I've increased muscle mas also, walking 7-10 miles per day whereas I dinn't exercise previously. I no longer eat red meat and consume mostly veggies, fish, and occasionally chicken. The fat% calculation cannot be correct.

[Bernieoc]

Replying to PopMusicGuy Perfect explanation. Spot on. The only approach that works for me. And The Obesity Code is a must read.