Assessing the fractional absorption of iron from edible insects

Sustainable diets are protective and respectful of biodiversity and ecosystems,
culturally acceptable, accessible, and affordable; nutritionally adequate, safe
and healthy; while optimizing natural and human resources. The fact that
insects are a common food source for 2 billion people already provides
excellent proof of its acceptability, especially in lower and middle income
countries. In this project, we will carry out experiments to investigate the
potential of insects as a source of iron when consumed as a common East African
meal.

The primary objective is to assess the relative bioavailability of iron from
insect added to either a high- or low-phytate meal in humans and its potential
to provide bioavailable iron. The secondary objective is to determine whether
addition of edible insects enhances or inhibits the absorption of native or
fortification iron from non-inhibitory or inhibitory meals

Single blind randomized partial Williams cross-over design

Freeze dried insects labelled with 2mg 57Fe will be added to refined
(non-inhibitory) maize porridge (test meal FeM-A) or to non-refined
(inhibitory) maize porridge (test meal FeM-D). Compared to two additional study
test-meals (FeM-B and FeM-E) which will contain 6.5 mg FeSO4 labelled with 3 mg
58FeSO4 added to either non-refined/ refined maize porridge (inhibitory/
non-inhibitory food matrix respectively), the test meals will enable us to
assess the relative bioavailability of iron from an insect-enriched low-phytate
meal (non-inhibitory) or high-phytate (inhibitory) food matrix. The last two
test meals (FeM-C and FeM-F) will contain half the amount of freeze dried
non-labelled insects plus 5.8 mg 54FeSO4 added to either refined
(non-inhibitory) or non-refined (inhibitory) maize porridge. These meals will
enable us to answer the question whether edible insects enhance/inhibit
absorption of native or fortificant iron in inhibitory and/or non-inhibitory
meals.

We do not anticipate that the experimental treatments will have any adverse
effects. Though previous studies involving edible insects are rare, the
European Food Safety Authority stated that house crickets are equivalent or
better than soy in supporting growth, as was shown in a study using weaned rats
(Committee 2015). Furthermore, although not systematically studied, house
crickets as a source of food seem a healthy and safe product. The existence of
20.000 farms in Thailand producing insects for human consumption indicates
crickets to be a safe food item. The food vehicle that will be used in this
study (porridge made from maize flour) is widely consumed in many parts of
Africa and Asia.

Participants will be expected to make eight visits to the research office.
Blood collection will be carried out by trained, experienced study nurses and
will be done on day 0 (screening time point), day 23, and day 39 (end point).
On day 7, 8, 9, 23, 24 and 25 participants will consume a test-meal during
breakfast and lunch time. During the screening visit, participants will be
asked to fill a questionnaire about their general health. Anthropometric
measurements will also be conducted. These data will contribute to baseline
data in addition to the evaluation for participation. It is foreseen that the
risks associated with participation in this study are negligible and the burden
is minimal. In addition, because each participant will be their own control,
disadvantages usually posed by being in the placebo group are not expected.

Experienced laboratory technicians and/or phlebotomists/nurses, using sterile
equipment and techniques, will do venous blood collection. A total amount of 30
mL of blood will be collected (10 mL at screening, baseline and endpoint). The
small risk of bleeding, infection and/or phlebitis after venepuncture will be
explained to the participants before blood collection. We will comply with
Dutch regulations for handling of biological specimens collected for research
purposes.