How to Track Progress on Keto: Measure Inches, Not Just Pounds

2020-01-22

In this recording

A six-minute explainer from January 2020 on how to tell whether keto is working.

[0:01] Most people track with a scale. The problem is water: you breathe it out, sweat it, pee it, drink it and eat it, and salt and potassium shift how much you hold.
[0:46] I said almost a gallon a day moves through you, so normal swings can be several pounds while you're trying to see one pound of fat loss a week. That's why people post that they ate well and are up two pounds.
[1:23] Menstrual cycles swing the scale too. If you weigh, do it at the same time each morning, with the same bathroom routine, and for women at the same phase of your cycle.
[2:06] Better: measure inches. The best is a DEXA scan, but measurements are the practical second best. Neck, arm, thigh and waist, each at the widest point.
[2:43] Volume is far less affected by water. And if you're gaining muscle while losing fat, the scale can stall while the tape still moves.
[3:22] A lot of people I've worked with were sure they weren't making progress until their clothes fit differently.
[3:49] Health metrics: blood pressure, cholesterol, resting heart rate. See your doctor before a major change and get a baseline blood test, including nutrient levels.
[4:37] Rechecking six months or a year later often shows improvements that boost your confidence.
[5:00] The yarn trick from my group: wrap yarn around waist, arm, thigh and neck, cut each, label it, hang them up. Redo it a month later and watch the strings get shorter.
[5:46] If you do weigh, a body-fat-estimating scale is useful compared against itself. Weigh less often, at a consistent time.

Watching this in 2026

The yarn strings were already in my 2018 basics video, where I told the story of a woman who taped yarn up on the wall and watching them get shorter (video UygKGoP_BtA). In 2020 I turned it into a method: four strings, labelled, a month apart. I still think it's the best low-tech tracker there is. It's free, it's visual, and it can't be thrown off by last night's salty dinner.

One number to correct. I said a gallon of water weighs seven pounds. A US gallon of water weighs more than that, so the point gets stronger, not weaker: daily water shifts can easily be bigger than a week of fat loss. That's the same thing I was explaining back in 2017 when I gained five pounds overnight (video f9P8BPWHc4U).

I'd soften one thing. "You should weigh yourself at the identical phase of your cycle" is good advice, but it assumes regular cycles. Perimenopause, contraception and other things change that. If your cycle isn't predictable, lean on the strings and the tape more than the scale.

The claim worth unpacking: get a baseline blood test

This is the part of the recording I'd most want a beginner to act on. Low-carb diets change blood lipids, and not all in the same direction for everyone.

The National Lipid Association statement (2019) says low- and very-low-carb diets lower triglycerides and raise HDL cholesterol, with a variable effect on LDL cholesterol.
A meta-analysis of 13 trials of at least 12 months (Bueno et al., 2013) found very-low-carb diets gave about 0.91 kg more weight loss than low-fat, with lower triglycerides and diastolic blood pressure, and higher HDL and LDL cholesterol.

A higher LDL is something you want to know about and talk through with your doctor, not discover by accident two years in. Without a "before" number, you can't tell whether it moved. There's more in cholesterol on keto and blood tests before starting.

If you take diabetes or blood-pressure medication, the baseline visit matters even more. In the non-randomised Virta study (Hallberg 2018), HbA1c fell from 7.6% to 6.3% and the intervention group used less diabetes medication. That's the point: doses often need to come down as eating changes, and that's your doctor's call, not mine. See keto with diabetes or blood-pressure medication.

Muscle and the scale

I said gaining muscle can mask fat loss on the scale. The evidence pages support the related point that higher-protein diets help you keep muscle while losing weight: energy-restricted high-protein diets gave modestly more fat loss and less loss of fat-free mass across 24 trials (Wycherley 2012). Inches tell you about both at once. See body recomposition.

Key points

The scale mixes fat with water, food and cycle changes. It's noisy on keto.
Measure neck, arm, thigh and waist at the widest point. Yarn strings work as well as a tape.
If you weigh, keep it consistent: same time, same routine, same point in your cycle where possible.
Get a baseline blood test before you start; low carb can raise LDL for some people (Bueno 2013).
On diabetes or blood-pressure medication? Your doctor needs to be in the loop from day one.