Opening the black box

I’ve had several requests for more detailed information on the foods I eat and how I arrive at my nutrient totals, so I’ve decided to change the format slightly. From now on I will be including the full nutritional information table I use to calculate the daily nutrition score (total calories, total grams of protein, carbs, etc.). The new table is below.

For each food I use the nutritional information provided on the package. If the information is for 100g and I’ve had 115g, I simply multiply the values by 1.15. If I make a food from scratch, such as the turkey cottage pie, I create a separate table where I add up the nutrient values for all the ingredients, then divide by the number of equal portions. When I eat out, I can usually find the nutritional information on the company’s website. I also have nutrition analysis software which I use with my sports nutrition clients, that gives the average nutrition for most foods, such as a fast food hamburger.

The problem with each of these methods is accuracy. Obviously when I eat out, I don’t weigh my food and if the company does not provide nutritional information, then I’m simply guessing. But even when I eat at home, the information on the back of packages can be surprisingly inaccurate. For example, the bag of the Genius bread I eat says 100g should have 269 kcal. However, when you add up all the nutrients and their calorie values, you get 249.4 kcal ((2.5g of protein x 4 kcal) + (45g of carbs x 4kcal) + (6.6g of fat x 9kcal)). That’s only 20 kcal off, but I find just about every product is like this, so at the end of the day my percent values for each nutrient only add up to 98% of the calories (I usually round up to get to 100%).

For exercise calories burned, I wear a Garmin watch with heart rate monitor chest strap when I exercise. This uses my height, weight, age and heart rate throughout the activity to calculate calories burned, so is fairly accurate. Like many people, I lead a fairly sedentary lifestyle, sitting at a desk most of the day and reading or watching TV in the evening. I do walk to and from the gym, and the track when I’m coaching, so I walk maybe 2 miles (3km) per day. Using my height, weight and age to calculate my resting metabolic rate (the calories burned just to keep breathing) gives about 1330kcal per day. Adding my sedentary lifestyle to this gives 665 kcal burned per day, for a total of 1995 kcal per day to maintain my weight (without exercise).

Feel free to add any other questions you may have in the comments below!

The Score for 9 February:

Calories: Protein: Carbs: Sugars: Fat: Sat Fat: Fibre:  
1985 131.90g 231.26g 131.76g 54.59g 17.25g 29.36g
27% 47% 25%
Calories burned through exercise: 287

 

What I ate:

Time Item Amount Calories Protein Carbs Sugars Fibre Fat Sat Fat
08:30 Centrum Multivitamin,  Vitamin E 400IU, Vitamin D 25 µg
Tap water 250mL 0 0.00 0.00 0.00 0.00 0.00 0.00
Scrambled eggs, 2 large 115g 150 14.49 0.00 0.00 0.00 10.35 2.88
with smoked salmon 36g 57 7.96 1.01 0.11 0.18 2.34 0.36
Chestnut mushrooms 92g 7 0.92 0.28 0.28 0.64 0.18 0.09
fried in butter 5g 37 0.03 0.06 0.03 0.00 4.11 2.61
Genius brown sliced gluten free bread, 2 slices toasted 64g 160 1.60 28.80 1.54 6.40 4.22 0.32
with butter 5g 37 0.03 0.06 0.03 0.00 4.11 2.61
and St Dalfour Raspberry fruit spread 24g 54 0.12 12.88 12.88 0.46 0.18 0.00
Black Tea 450mL 0 0.00 0.00 0.00 0.00 0.00 0.00
12:45 Homemade turkey cottage pie topped with potato and parsnip mash 250g 397 40.59 39.75 10.48 6.80 7.06 1.23
with ketchup 17g 17 0.20 3.94 3.88 0.00 0.02 0.00
Small vine ripened tomatoes 95g 19 0.67 2.95 2.95 0.95 0.29 0.10
Kiwi, 2 medium peeled 115g 63 1.27 12.19 11.85 2.19 0.58 0.00
Yakult light 65mL 27 0.90 6.60 3.60 0.00 0.00 0.00
16:00 Trek Peanut Power energy bar 55g 203 10.20 25.70 21.10 3.00 6.00 1.00
Golden delicious apple 100g 53 0.40 11.80 11.80 1.80 0.10 0.00
Black tea with skimmed milk and sugar 450mL 62 3.40 12.00 12.00 0.00 0.10 0.00
16:45 Javelin training
18:15 Baked chicken breast 107g 113 25.68 0.00 0.00 0.00 1.18 0.32
Merchant Gourmet red and white quinoa 110g 203 6.71 31.46 1.65 4.40 4.62 0.55
Broccoli, microwaved 100g 40 4.30 3.20 1.90 2.50 0.60 0.20
Cucina Glaze with Balsamic vinegar of Modena 10g 26 0.05 6.40 4.80 0.05 0.05 0.00
18:45 Starbucks steamed skimmed milk with vanilla shot Tall 146 10.50 25.40 25.10 0.00 0.30 0.20
21:00 Lindt Excellence 70% Cocoa chocolate bar, 2 squares 20g 113 1.90 6.80 5.80 0.00 8.20 4.80

Image Copyright: <a href=’http://www.123rf.com/profile_dolgachov’>dolgachov / 123RF Stock Photo</a>

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