White Bread

Food · Grain · Food, Typed Supps

A quarter of a day’s folate and a third of your iodine, by law rather than by nature.

Stage by stage

Fortified by law (The flour): Folic acid, iodised salt and thiamin are added by regulation, not left over from the wheat.
Folate (Small intestine): 357 mcg per 100 g — a quarter of a day in two slices.
Iodine (Thyroid): 61.3 mcg per 100 g, added to address a re-emerged deficiency.
Thiamin (Nervous system): 0.648 mg per 100 g, mandatory since 1991 to reduce alcohol-related encephalopathy.

Timing

Nothing to time. The relevant question is whether the bread you eat is covered by the mandate — organic and gluten-free usually are not.

Time to effect

2–3 years: How quickly neural tube defect rates fell after the 2009 mandate.
Per 2 slices: Roughly 210 mcg folate, 37 mcg iodine and 0.39 mg thiamin.

Allergens

Contains: Gluten. May contain: Eggs, Milk, Sesame, Soya. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher. Depends on the product: Low-FODMAP.

Satiety

100 on the satiety index, where white bread is 100 — moderate. Measured by Holt et al. (1995).

Environmental footprint

1.6 kg CO2e and 648 litres of freshwater per kg, matched to "Wheat & rye" in Poore & Nemecek (2018), Science 360.

Cost band

Cheap — roughly £3 per kg, as a band midpoint rather than a price.

Key nutrients

Folate
Thiamin
Iodine

Nutrition per 100g

Calories: 251
Protein: 9.5g
Carbohydrate: 46.2g
of which sugars: 3.1g
Fat: 2g
of which saturated: 0.3g
Fibre: 3.2g
Sodium: 439mg

Food vs. supplement

Folic acid supplements only reach people who know they may become pregnant. Fortified bread reaches everyone, which is why the neural tube defect reduction showed up in the population data and not just in planned pregnancies.

Kitchen tip

If you have moved to gluten-free bread, you have probably lost most of your folate, iodine and thiamin from bread — the mandate does not cover it.

Common myth

“White bread has had all the goodness stripped out of it.” In reality: Refining does remove the germ and bran, and with them most of the fibre and minerals — that part is true, and it is why wholemeal is the better choice. But the folate, iodine and thiamin on the panel were put back by law, and at 357 mcg of folate per 100 g white bread is one of the largest folate sources in the Australian diet. The argument for wholemeal is fibre, not B vitamins.