Background: Pastoralists live in challenging environments, which may be accompanied by unique
activity, energy, and water requirements.
Aim: Few studies have examined whether the demands of pastoralism contribute to differences in total
energy expenditure (TEE) and water turnover (WT) compared to other lifestyles.
Subjects and methods: Accelerometer-derived physical activity, doubly labelled water-derived TEE and
WT, and anthropometric data were collected for 34 semi-nomadic Daasanach adults from three northern
Kenyan communities with different levels of pastoralist activity. Daasanach TEEs and WTs were compared
to those of other small-scale and industrialised populations.
Results: When modelled as a function of fat-free-mass, fat-mass, age, and sex, TEE did not differ between
Daasanach communities. Daasanach TEE (1564–4172 kcal/day) was not significantly correlated with
activity and 91% of TEEs were within the range expected for individuals from comparison populations.
Mean WT did not differ between Daasanach communities; Daasanach absolute (7.54 litres/day men; 7.46
litres/day women), mass-adjusted, and TEE-adjusted WT was higher than most populations worldwide.
Conclusions: The similar mass-adjusted TEE of Daasanach and industrialised populations supports the
hypothesis that habitual TEE is constrained, with physically demanding lifestyles necessitating trade-offs
in energy allocation. Elevated WT in the absence of elevated TEE likely reflects a demanding active
lifestyle in a hot, arid climate.
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High energy requirements and water throughput of adult Shuar forager‐horticulturalists of Amazonian Ecuador
We measured total energy expenditure (TEE; kcal/d) and water throughput (L/d) among Shuar forager‐horticulturalists from Amazonian Ecuador to compare their daily energy and water demands to adults in other small‐scale and industrialized populations.
TEE and water throughput were measured using the doubly labeled water method among 15 Shuar adults (eight women, seven men; age range 18‐60 years) living in a relatively remote village. We used multiple regression to assess the effects of anthropometric variables (body size, fat free mass, age, and sex) on TEE and water throughput. We also compared Shuar TEE and water throughput to those of other small‐scale and industrialized societies.
TEE among Shuar adults (men: 4141 ± 645 kcal/d, women: 2536 ± 281 kcal/d) was most strongly correlated with fat free mass. Estimated physical activity levels (PAL) calculated as (TEE/estimated BMR), were greater for men (2.34 ± 0.29) than women (1.83 ± 0.14,
TEE and PAL of Shuar men are among the highest recorded during normal daily life, and likely reflect both high levels of physical activity and cultural dietary practices. Drinking large amounts of chicha, a traditional carbohydrate‐rich drink made from manioc, likely contributes to the high levels of water throughput among Shuar men, and may contribute to elevated TEE.
- PAR ID:
- 10462480
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- American Journal of Human Biology
- Volume:
- 31
- Issue:
- 2
- ISSN:
- 1042-0533
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Low total energy expenditure (TEE, MJ/d) has been a hypothesized risk factor for weight gain, but repeatability of TEE, a critical variable in longitudinal studies of energy balance, is understudied. We examine repeated doubly labeled water (DLW) measurements of TEE in 348 adults and 47 children from the IAEA DLW Database (mean ± SD time interval: 1.9 ± 2.9 y) to assess repeatability of TEE, and to examine if TEE adjusted for age, sex, fat-free mass, and fat mass is associated with changes in weight or body composition. Here, we report that repeatability of TEE is high for adults, but not children. Bivariate Bayesian mixed models show no among or within-individual correlation between body composition (fat mass or percentage) and unadjusted TEE in adults. For adults aged 20–60 y (
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p < .001). Herder TEEDLWwas significantly higher than that of hunter gatherer (p = .0014) and market (p < .0014) economy populations; however, herder TEEDLWwas not different from that of farming populations (p = .91).Conclusion High TEE and low caloric intake among herders reflect the extreme demands placed on herders during the annual herd round up. Although TEEDLWwas similar between cold climate herders and hot climate farming populations, there are likely differences in how that TEE is comprised, reflecting the local ecologies of these populations.
