title: Leisure-time physical activity and nutrition: a twin study.
abstract: OBJECTIVE
  To determine the association between long-term leisure-time physical activity/inactivity and eating behaviours in twin pairs discordant for physical activity for 30 years.
  
  
  METHODS
  Co-twin control design with cross-sectional data collection using questionnaire on eating habits and 5 d food diary. Differences in eating behaviours between physically active and inactive co-twins were analysed with pairwise tests.
  
  
  METHODS
  Finland.
  
  
  METHODS
  Sixteen same-sex twin pairs (seven monozygotic and nine dizygotic, mean age 60 years) discordant for physical activity, selected from the Finnish Twin Cohort on the basis of physical activity discordance for 30 years, blinded to their possible differences in eating behaviours.
  
  
  RESULTS
  The eating habits questionnaire revealed that physically active co-twins more frequently reported that it is easy to eat according to need, whereas overeating and/or restrictive eating was more common among the inactive co-twins (P = 0·035). Avoiding calories was more common among the active than inactive co-twins (P = 0·034). Based on food diaries the physically active co-twins had daily energy intake on average 15·5 kJ/kg higher than their inactive co-twins (P = 0·030). The active co-twins also had a higher intake of vitamin C (P = 0·004), total water (P = 0·044), legumes and nuts (P = 0·015) and sweets (P = 0·036), as well as a lower energy-adjusted intake of meat (P = 0·013).
  
  
  CONCLUSIONS
  The physically active persons seem to eat more but not necessarily healthier food. However, habitual physical activity may help in eating according to need and in reaching and maintaining a healthy body composition. Therefore, it is necessary to incorporate both dietary and physical activity advice into health counselling.
authors.affiliation: Department of Health Sciences, University of Jyväskylä, PO Box 35(LL), FIN-40014, Finland. mirva.l.a.rintala@jyu.fi
authors.forename: Mirva
authors.initials: M
authors.lastname: Rintala
authors.forename: Arja
authors.initials: A
authors.lastname: Lyytikäinen
authors.forename: Tuija
authors.initials: T
authors.lastname: Leskinen
authors.forename: Markku
authors.initials: M
authors.lastname: Alen
authors.forename: Kirsi H
authors.initials: KH
authors.lastname: Pietiläinen
authors.forename: Jaakko
authors.initials: J
authors.lastname: Kaprio
authors.forename: Urho M
authors.initials: UM
authors.lastname: Kujala
mesh_terms: D000368:Aged; D001823:Body Composition / Q000502:physiology; D003430:Cross-Sectional Studies; D015930:Diet Records; D002149:Energy Intake; D015444:Exercise / Q000502:physiology*; D005247:Feeding Behavior; D005260:Female; D005387:Finland; D015438:Health Behavior; D006293:Health Promotion / Q000458:organization & administration; D006801:Humans; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009747:Nutritional Physiological Phenomena / Q000502:physiology*; D009765:Obesity / Q000517:prevention & control; D012527:Satiation / Q000502:physiology; D014429:Twins, Dizygotic / Q000502:physiology; D014430:Twins, Monozygotic / Q000502:physiology