A talk I gave on food tracking to the Melbourne Quantified Self Meetup.
..........................................................................................................Nine months of foodLars YenckenMelbourne Quantified Self Meetup17th October 2013
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..........................................................................................................Attempts at measurement▶ Location: GPS tracking over time▶ Habits: daily habits like meditation▶ Writing: patterns and themes in my writing▶ Coding: how long I spend editing what▶ Food: what I eat when
..........................................................................................................Earlier this year...▶ Overweight at 94 kg▶ In at-risk category for diabetes▶ Active-ish, but not fit▶ Long hours of computer work
..........................................................................................................More generally▶ Modern food▶ Quantity: our bodies mislead us, food is abundant*▶ Quality: food is optimised for taste, not health▶ Intolerance: our diet contains vast numbers of ingredients▶ Modern living▶ Sedentary workplaces: we sit, all day
..........................................................................................................My weightHistoric range 87-105 kgJan 2013 94 kg
..........................................................................................................My weightHistoric range 87-105 kgJan 2013 94 kgTarget (bet) 85 kg
..........................................................................................................ToolsEasy Diet Diary Bathroom scales
..........................................................................................................Binges?
..........................................................................................................How it unfolded...1. I became hungry, very hungry, and tired2. To eat more, I drifted to a healthier range of foods3. To eat more, I increased my exercise4. I lost about 12 kg5. My energy largely returned, and I found myself “fit”
..........................................................................................................2012 201380 85 90 95Weight over timeDateWeight (kg)
..........................................................................................................Dataset
..........................................................................................................▶ Food▶ 185 days of meals▶ 11.5 items/day on average▶ 550 distinct food items (manually relabelled)▶ Weight and macronutrients per item▶ Weight▶ 223 days of body mass and body fat percentage▶ Exercise▶ 185 days, still locked in software
..........................................................................................................What did I eat?
..........................................................................................................Most common foodsFood Countbread 88protein 85alcohol-beer 84crispbread 82coffee 73milk-cow 70vegies-tomato 67vegies-cucumber 62fruit-banana 61salad 53
..........................................................................................................How much do I eat?
..........................................................................................................0 5000 10000 15000 20000 250000e+00 2e−05 4e−05 6e−05 8e−05 1e−04Daily energy consumption (gross)Energy (KJ)Frequency
..........................................................................................................How much can I eat?
..........................................................................................................Tomorrow’s weight change based on how much I eat today(wt+1 − wt) = α(et− ebase) + noise
..........................................................................................................> summary(lm(w$weightdiff ~ w$energy))...Coefficients:Estimate Std. Error t value Pr(>|t|)(Intercept) -4.545e-01 1.505e-01 -3.020 0.00310 **w.e$energy 4.071e-05 1.458e-05 2.791 0.00613 **---Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1Residual standard error: 0.6491 on 118 degrees of freedom(53 observations deleted due to missingness)Multiple R-squared: 0.06194, Adjusted R-squared: 0.05399F-statistic: 7.791 on 1 and 118 DF, p-value: 0.006125
..........................................................................................................ebase11.2 MJα 40.7 g per MJ(24.6 MJ per kg)fat 37 MJ per kg
..........................................................................................................ebase11.2 MJα 40.7 g per MJ(24.6 MJ per kg)fat 37 MJ per kgbut... missing exercise data
..........................................................................................................Do large breakfasts help?
..........................................................................................................0 2000 4000 6000 80000 5000 10000 15000 20000Breakfast vs rest of dayBreakfast (kJ)Rest of day (kJ)
..........................................................................................................How much meat do I eat?
..........................................................................................................▶ Manually tagged foods containing meat▶ Results▶ 20% of days meat free▶ 63% of meals meat free
..........................................................................................................Breakfast Lunch Snacks DinnerVegetarian 141 (78%) 80 (47%) 145 (91%) 57 (35%)With meat 39 (22%) 89 (53%) 14 (9%) 105 (65%)Total 180 169 159 162
..........................................................................................................What foods do I eat together?
..........................................................................................................ItemsetsSupport Food46 vegies-cucumber + vegies-tomato37 crispbread + vegies-tomato37 crispbread + vegies-cucumber34 crispbread + vegies-cucumber + vegies-tomato32 fruit-banana + protein32 bread + vegies-tomato30 alcohol-beer + vegies-tomato30 alcohol-beer + vegies-cucumber29 coffee + protein29 bread + vegies-cucumber
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..........................................................................................................How much caffeine do I consume?
..........................................................................................................Jan 052013Feb 082013May 012013Jun 032013Jul 222013Sep 012013Oct 0120130 20 40 60 80 100Caffeine consumption per day (rolling mean)Caffeine (mg)
..........................................................................................................Data wierdness▶ Varying granularity of meals▶ Low-density foods sometimes left out▶ Not enough detail for intolerances
..........................................................................................................In retrospect▶ Great benefits▶ Measurement has helped me become healthy▶ Much unresolved▶ What foods make me most alert?▶ Am I intolerant to foods I eat?▶ Need matching datasets to answer more questions
..........................................................................................................Thanks!
larsyencken
jrom
lauravandoore
jcasabona
shpigford
robhawkes
philhawksworth
dougneiner
lara
orderedlist
marcelosomers
kneath
jonyablonski