ANT214H5 Chap.2 Nutrition Across the Life Course
Nutrition Across the Life Course
Put timing inside the causal claim
A life-course approach asks when an exposure occurs, how long it lasts, whether its effects accumulate, and whether later conditions modify the outcome. Nutritional needs and vulnerabilities change across gestation, infancy, childhood, adolescence, adulthood and older age. The same restriction can therefore have different consequences depending on developmental stage and duration.
A strong response does not merely list stages. It names a process such as growth, immune development or reproductive investment and explains why timing changes the relationship between exposure and outcome.
Distinguish critical, sensitive and cumulative models
A critical-period claim proposes that exposure within a bounded developmental window produces an effect that later conditions cannot fully reverse.
A sensitive-period claim allows greater influence during one window without making later change impossible. A cumulative model focuses on repeated or sustained advantage and disadvantage. These models predict different evidence.
To distinguish them, compare trajectories, not just end points, and ask whether later improvement narrows, removes or fails to alter the difference associated with early exposure.
Analyse growth as allocation
Growth is a biological process embedded in household resources, disease environments, caregiving and social priorities.
Energy and nutrients may be allocated among maintenance, activity, growth and reproduction, with constraints changing across the life course. Slower growth is not explained by food quantity alone when infection raises needs or reduces absorption. Conversely, an average growth measure cannot specify the household relations that generated exposure.
Link the bodily process to the social distribution of food, time, care and risk.
Use developmental plasticity carefully
Developmental plasticity describes the capacity of one genotype to produce different phenotypes under different conditions. It can help explain how early environments shape later physiology, but it is not proof that every response is adaptive.
Claims about prediction or mismatch require evidence about the cue, the resulting phenotype, the later environment and the fitness or health consequence.
Where those links are missing, a bounded account should describe the observed association and plausible pathway without turning an attractive evolutionary story into a settled mechanism.
Follow intergenerational pathways
Nutrition can cross generations through maternal physiology, caregiving, resource distribution, social position and inherited or epigenetic processes.
These mechanisms should be separated because they imply different interventions and evidence. An observed association between maternal and child outcomes does not identify which pathway operated. Trace the sequence from maternal conditions to fetal or infant exposure, then to growth or later risk, while considering shared environment and confounding.
A life-course conclusion is strongest when it states the relevant window, mechanism, later modifier and uncertainty.
Trajectory check
Draw two plausible developmental trajectories from the same early exposure: one in which later resources permit recovery and one in which disadvantage accumulates. Label the biological process and social condition at each divergence.
The exercise makes timing and modification visible and prevents adult outcome from being read backwards as proof of one childhood pathway.
Revision should preserve both developmental timing and the possibility that changed later conditions redirect the observed pathway.
What this chapter covers
- 01
Critical periods
- 02
Growth and development
- 03
Maternal nutrition
- 04
Developmental plasticity
- 05
Intergenerational effects
Worked example · free
Worked example: Nutrition Across the Life Course
- 2Place the nutritional exposure inside a defined developmental window and trajectory.
- 3Compare recovery, persistence and accumulated disadvantage under changed later conditions.
- 3Separate physiological transmission from continuing household or social exposure across generations.
Key terms
- Life Course
- An approach that explains health through the timing, duration and accumulation of exposures across development.
- Sensitive Period
- A developmental interval during which an exposure has greater influence, while later modification remains possible.
- Developmental Plasticity
- The capacity for development to produce different phenotypes in response to environmental conditions.
- Intergenerational Effect
- An influence transmitted across generations through biological, behavioural, social or material pathways.
Nutrition Across the Life Course FAQ
What makes a claim life-course rather than chronological?
It explains why timing, duration, accumulation or later modification changes an outcome. Listing infancy, childhood and adulthood is not enough unless the answer traces a developmental process and identifies the evidence that distinguishes competing models.
Is developmental plasticity always adaptive?
No. A developmental response can reflect constraint, damage or a trade-off, and an apparently useful response in one setting may carry costs elsewhere. Adaptive claims need evidence about cues, phenotype, later environment and consequence.
Exam move
Rebuild one life-course trajectory from memory, marking exposure windows, accumulation and later modification. Change the timing of one exposure and explain why the predicted outcome changes.
