Advances in assessing dietary intake: Lessons from technology and nutritional epidemiology

The food we eat affects our health. This premise is at the very core of nutrition science and dietetic practice. To advance practice in dietetics, it imperative to explore understand what people eat. Finding out fundamental everyday dietitians nutritionists. However, as scientists, important assumptions methods that underlie issue Nutrition Dietetics, a journal with stated aim “to human professional dietetics”1 provides us opportunity reflect on current dietary assessment consider how technical advances those techniques can inform research ability provide relevant advice requires firm evidence base. Evidence provided by nutritional epidemiology, which based first sentence – intake influences health outcomes, either through prevention or causation. There are still much unknown about diet-related aetiology disease effectively treat prevent intervention. Applying principles epidemiology observational experimental study designs population-based surveys examine these questions. It therefore method from epidemiological perspective validity conclusions made risk chronic effectiveness interventions. In studies, diet typically measured an exposure intermediate outcome for long-term outcomes. While measurement population exposures such radiation, tobacco even alcohol has its challenges, more complex. Diet cannot be single exposure, nutrients interact varies over time.2 Yet make valid intervention relies being reliable. A systematic review all randomised control trial dietitian counselling (outside hospital environment) published up October 2016 found only 12 26 included studies attempted measure change because intervention.3 base reporting clarity interventions thus strengthening. Technological have facilitated large scale but need ensure followed. enhance measure, strategies reduce random error occurring each three stages considered. stage estimation individuals. usually conducted history, 24-hour recall, record, records, frequency questionnaire (FFQ), their own uses limitations terms measuring usual intake.2 Where possible, should validated appropriate populations use biomarkers other techniques. Stage two analysis composition estimated intake. calculate consumed databases computerised software programs access databases. computers results several decimal places, remember data originated laboratory analyses whole foods ingredients, inherent limitations. final comparison nutrient intakes established standards reference values selection guides. professionals appreciate sources phases process, clearly acknowledged drawing scientific studies. Given been criticised lack precision measures,4 methodological improve accuracy serve strengthen confidence conclusions. Several papers this contribution understanding application assessment. Further, clear detailed needed allow readers draw articles Clarke colleagues5 Lancaster colleagues6 particular, exemplify best description methods. Both sufficient detail they could replicated, researchers also documented database version used not simply program step my experience too often omitted yet essential making meaningful comparisons paper six recalls collected via Australian Automated Self-Administered tool (ASA-24) across 10-week They Eating Survey FFQ assess preceding 3 months. relatively low-intensity comprised 1-hour sessions Accredited Practising Dietitian (APD) emphasis increasing quality fruit vegetable serves. was designed achieve body composition, team determine whether anthropometric dependent resulted increased positive changes women men, however linear mixed models were independent controlled trials where condition treatment, vital accurately compliance order presence effect due non-compliance diet. By collecting data, authors demonstrated achieved. Thus, if mediator hypothesised, confident APD responsible results. reinforces findings meta-analysis showed individualised care successful achieving weight loss.7 Nutritional strengthened “big-data” approach research: computerisation led sets comprising multiple variables.8 Fayet-Moore colleagues9 secondary National Physical Activity survey 2011-2012, relied automated pass collect recalls. examined way snacks defined experts participants. Snacks (objectively) differed subjective descriptions snacking completing surveys. appears consumers likely label discretionary snacks, while majority objectively actually would classified Guide Healthy (AGHE). implications aware define constitutes “snack” interpret do apply definitions caution. literacy applications (apps) moved requiring expertise nutritionists consumers. article further assessing studying diary app 55-75 years age. Participants kept 3-day record interviewed confirm data. Researchers errors consisted missing items implausible quantities. expert knowledge design set adjustments automatically applied raw give similar laboriously dietitian. providing new recording technology. Other investigated university students. McCartney colleagues10 147 students enrolled various degrees who participating undergraduate course Australia. recorded period weekday calculated number standard serves groups according AGHE. Importantly then cost beverages median $12.42. Those worked 20 hours week had higher ($15.83) than less per ($12.11) unemployed ($11.43). Pelly Wright11 international sporting event held Taipei, including high proportion participants non-Western countries. intake, that, despite high-level competition, most following special sport diets low calcium vegetables. Three setting status. Lee colleagues12 described cross-sectional patients cardiology ward examining any followed some type diet, prescribed unnecessarily restrictive contributing prevalence malnutrition group. care, communication messages broadly protect elders. Another study, Kaddoura colleagues,13 PG-SGA status intensive unit (ICU) patients. no statistically significant relationship between mortality, ICU length stay rate mechanical ventilation, significantly 1 longer 36% malnourished upon admission (according after adjusting APACHE score, age comorbidities). Wright colleagues14 reported 31% older (60 years+) admitted predominantly elective reasons private India, however, 44% during admission, half at-risk Measurement exposes issues hospitals communities opportunities advocacy dietetics. contains dietetics ways. Roesler colleagues15 qualitative exploration lived experiences choose VLCD products. raises concerns of, given self-management products rather receiving care. Delaney colleagues16 interviews practices around prescribing rights involved Pancreatic Enzyme Replacement Therapy (PERT). Their existing role medication therapy recommendations practitioner patient education use. Findings add argument necessary titrated amount components optimal Nagy colleagues17 looks extent client-dietitian embedded curriculum credentialing dietitians. document outlines semi-structured telephone academics perceived importance consistently throughout curriculum. Dietary continually evolving science. illustrates leading edge using enhanced technology These possess conducting reliable I argue seeking diet-disease relationship. same require statistician economist, advocate include nutritionist veracity