ALGEMENE VOEDINGSLEER EN
SPORTVOEDING
ALGEMENE VOEDINGSLEER
NUTRITION AND SPORTS NUTRITION: GENERAL NUTRITION
CHAPTER 0 – GENERAL INTRODUCTION
Health = balance energy supply and energy expenditure
Food science
ð ‘The nature of food, the causes of deterioration, the principles underlying food processing, and
the improvement of foods for the consuming public.’
- Bioengineer reference: designing and modifying food products at a molecular and
structural level
- Food technology: how food is processes, preserved and manufactured
- Food safety: ensures that food is safe for consumption by studying pathogens,
contamination and quality control
Nutrition science
ð ‘It is the study of the processes by which organisms ingest, digest, absorb, transport, utilize,
and excrete food substances, and how these processes relate to health and disease.’
- Biomedical reference: studies how nutrients interact with the body at the cellular and
systemic levels
- Health: focuses on how diet influences overall health, disease prevention and wellness
- Clinical nutrition/public health: applies knowledge in medical settings (clinical nutrition)
and community-wide initiatives (public health nutrition) to improve population health
Link nutrition and health
ð Nutrient deficiencies (iron, iodine, vit B12…) -> chronic degenerative diseases (CVD, cancer,
obesity, diabetes, osteoporosis…)
ð Importance of a balanced diet and sufficient exercise
- Food: hundreds of substances in our food with varying effects on…
- Energy supply: … dozens of physiological processes that are active in our body and
maintain our health…
- Nutritional status: …involved in complex mechanisms that can lead to disease (pathways
of disease)…
- Health: …which often take place over a period of several decades
ð David Barker (1938 – 2013): programming
- Process by which events during critical periods of development can alter the structure
and function of the organism
o Example: fetal malnutrition can affect prenatal growth, potentially shaping long-
term health outcomes
1
, - Dutch hungerwinter study: ongoing study investigating the effects of wartime famine in
utero on later health
o Showing that malnutrition during pregnancy has lasting consequences for the later
health of the child and generations afterwards
o Effects of hunger depend on the moment of pregnancy
Loss of healthy years of life due to nutritional imbalance – disability adjusted life years (DALY’s)
ð 1 DALY = 1 lost year of ‘healthy’ life
- Sum of DALYs across the population or the burden of disease -> measurement of the gap
between current health status and an ideal health situation where the entire population
lives to an advances age, free of disease and disability
- DALYs = sum of the years of life lost due to premature mortality (YLL) and the years lived
with a disability (YLD)
2
,Definitions
ð Nutrition (voeding) = influence of food, nutrients and bioactive food components on the body
ð Food safety (voedselveiligheid) = conditions and practices that preserve the quality of food to
prevent contamination and food-borne illnesses
ð Food security (voedselzekerheid) = exists when all people, at all times, have physical and
economic access to sufficient, safe and nutritious food to meet their dietary needs and food
preferences for an active and healthy life
Nutrients
ð Each nutrient has a certain role to play in the biology of the body
ð Example essential nutrient = iron
IRON
ð One of the most common metals on earth (but common deficiency in humans)
ð Without iron -> no oxygen transport through the body possible
ð Iron from food -> 2 forms: haem iron & non-haem iron
- Included in duodenum -> absorption can be influenced by many factors
- Iron deficiency will stimulate iron absorption (hormone: hepcidin)
ð Increased risk deficiency: children, adolescents, pregnant women and premenopausal
women + pathological disease (bleeding, surgery)
ð Iron deficiency can lead to anemia
- Iron = carrier of oxygen to tissues from longs by rood blood cells hemoglobin as a
transport medium for electrons within cells and as an integrated part of important enzyme
systems in various tissue
ð Human body -> average of 3-4 grams of iron
- Functional iron in hemoglobin in RBC (60%)
- Ferritin (iron reserve in liver, spleen, bone marrow -> used for RBC production) (25%)
- Myoglobin (protein in muscle cells that stores oxygen) (7%)
- Iron in various enzymes that need iron to function (5%)
- Transport iron in the body, bounded to transferrin (3%)
ð Iron requirements: growth, pregnancy, lactation
Functional iron
ð Iron as part of different hemoproteins: several functions
- Oxygen carriers: hemoglobin and myoglobin are essential for oxygen transport and
storage, ensuring that tissues receive oxygen
- Electron transport chain: cytochromes a, b, c are involved in the electron transport chain,
facilitating the production of ATP (primary form of energy used by cells)
- Metabolism: cytochrome P450 enzymes are vital for the detoxification and metabolism of
various substances, protecting the body from harmful compounds
ð Iron-sulfur proteins
- Redox enzymes (electron transfer): xanthine oxidase (purine degradation) – succinate
dehydrogenase (TCA cycle)
- Non-redox enzymes (no electron transfer, no oxidation of reduction): aconitase (TCA
cycle)
3
, Iron food sources
- Heme iron (higher bioavailability, absorbs more directly): animal foods (lamb, beef,
salmon, chicken, tuna, sardines, eggs)
- Non-heme iron: plant foods (tofu, oats, cereals, chickpeas, nuts, brown rice, raw spinach)
Iron absorption
ð Bioavailability of a nutrient: the proportion of that nutrient ingested from a particular food or
meal that can be absorbed and is available for utilization by the body of normal metabolic
function
ð Iron is absorbed by the enterocytes of mainly the duodenum and the upper part of the jejunum
ð Different absorption mechanisms for non-heme
and heme iron)
- Non-heme iron: reduction from ferric iron
(Fe3+) to ferrous iron (Fe2+) by ferrous
reductase enzyme (ferrireductase) -> Fe2+
absorbed via divalent metal transporter 1
(DMT-1, located on membrane of enterocytes)
- Heme iron: own transport system via heme
carrier protein 1 (HCP-1, protein on
membrane of enterocytes) -> heme iron
further broken down into Fe2+ and bilirubin
(byproduct) by hemoxygenase 1 (Hox1)
o Fe2+ stored as ferritin or transported out
of enterocytes into blood via ferroportin where it binds to transferrin for distribution
ð Iron in enterocyte can follow 2 possible pathways
- Iron abundance status (sufficient iron in the body): iron will bound to ferritin and remain in
the cell -> will disappear together with the enterocyte after a few days and end up in the
stool
- Iron limiting state (varying degrees of iron deficiency): iron will be transferred from the
enterocyte to the blood via a specific transport protein (ferroportin – located in the
membrane) -> during transport Fe2+ is converted to Fe3+ by enzyme hephaestin
(ferroxidase) -> in the blood it will bind to transferring and be transported throughout the
body
ð Iron absorption in the intestine
- Average absorption non-heme iron: 5-15%
o Promote absorption: vit C (vegetables and fruits), MFP factor (meat, fish)
o Counteract with absorption: polyphenols, phytates, oxalates (chelation: formation
of an insoluble complex with iron -> no longer bind to DMT-1 receptor) – Cu2, Zn2,
Mg2, Ca2 (competition)
- Average absorption heme iron: 20-30%
o Counteract with absorption: calcium
ð On average 10% of dietary iron is absorbed
- Typical diet: 10-20mg of iron
- Small portion is absorbed: 1-2mg
o Depending on factors like dietary composition, iron status and physiological needs
4
SPORTVOEDING
ALGEMENE VOEDINGSLEER
NUTRITION AND SPORTS NUTRITION: GENERAL NUTRITION
CHAPTER 0 – GENERAL INTRODUCTION
Health = balance energy supply and energy expenditure
Food science
ð ‘The nature of food, the causes of deterioration, the principles underlying food processing, and
the improvement of foods for the consuming public.’
- Bioengineer reference: designing and modifying food products at a molecular and
structural level
- Food technology: how food is processes, preserved and manufactured
- Food safety: ensures that food is safe for consumption by studying pathogens,
contamination and quality control
Nutrition science
ð ‘It is the study of the processes by which organisms ingest, digest, absorb, transport, utilize,
and excrete food substances, and how these processes relate to health and disease.’
- Biomedical reference: studies how nutrients interact with the body at the cellular and
systemic levels
- Health: focuses on how diet influences overall health, disease prevention and wellness
- Clinical nutrition/public health: applies knowledge in medical settings (clinical nutrition)
and community-wide initiatives (public health nutrition) to improve population health
Link nutrition and health
ð Nutrient deficiencies (iron, iodine, vit B12…) -> chronic degenerative diseases (CVD, cancer,
obesity, diabetes, osteoporosis…)
ð Importance of a balanced diet and sufficient exercise
- Food: hundreds of substances in our food with varying effects on…
- Energy supply: … dozens of physiological processes that are active in our body and
maintain our health…
- Nutritional status: …involved in complex mechanisms that can lead to disease (pathways
of disease)…
- Health: …which often take place over a period of several decades
ð David Barker (1938 – 2013): programming
- Process by which events during critical periods of development can alter the structure
and function of the organism
o Example: fetal malnutrition can affect prenatal growth, potentially shaping long-
term health outcomes
1
, - Dutch hungerwinter study: ongoing study investigating the effects of wartime famine in
utero on later health
o Showing that malnutrition during pregnancy has lasting consequences for the later
health of the child and generations afterwards
o Effects of hunger depend on the moment of pregnancy
Loss of healthy years of life due to nutritional imbalance – disability adjusted life years (DALY’s)
ð 1 DALY = 1 lost year of ‘healthy’ life
- Sum of DALYs across the population or the burden of disease -> measurement of the gap
between current health status and an ideal health situation where the entire population
lives to an advances age, free of disease and disability
- DALYs = sum of the years of life lost due to premature mortality (YLL) and the years lived
with a disability (YLD)
2
,Definitions
ð Nutrition (voeding) = influence of food, nutrients and bioactive food components on the body
ð Food safety (voedselveiligheid) = conditions and practices that preserve the quality of food to
prevent contamination and food-borne illnesses
ð Food security (voedselzekerheid) = exists when all people, at all times, have physical and
economic access to sufficient, safe and nutritious food to meet their dietary needs and food
preferences for an active and healthy life
Nutrients
ð Each nutrient has a certain role to play in the biology of the body
ð Example essential nutrient = iron
IRON
ð One of the most common metals on earth (but common deficiency in humans)
ð Without iron -> no oxygen transport through the body possible
ð Iron from food -> 2 forms: haem iron & non-haem iron
- Included in duodenum -> absorption can be influenced by many factors
- Iron deficiency will stimulate iron absorption (hormone: hepcidin)
ð Increased risk deficiency: children, adolescents, pregnant women and premenopausal
women + pathological disease (bleeding, surgery)
ð Iron deficiency can lead to anemia
- Iron = carrier of oxygen to tissues from longs by rood blood cells hemoglobin as a
transport medium for electrons within cells and as an integrated part of important enzyme
systems in various tissue
ð Human body -> average of 3-4 grams of iron
- Functional iron in hemoglobin in RBC (60%)
- Ferritin (iron reserve in liver, spleen, bone marrow -> used for RBC production) (25%)
- Myoglobin (protein in muscle cells that stores oxygen) (7%)
- Iron in various enzymes that need iron to function (5%)
- Transport iron in the body, bounded to transferrin (3%)
ð Iron requirements: growth, pregnancy, lactation
Functional iron
ð Iron as part of different hemoproteins: several functions
- Oxygen carriers: hemoglobin and myoglobin are essential for oxygen transport and
storage, ensuring that tissues receive oxygen
- Electron transport chain: cytochromes a, b, c are involved in the electron transport chain,
facilitating the production of ATP (primary form of energy used by cells)
- Metabolism: cytochrome P450 enzymes are vital for the detoxification and metabolism of
various substances, protecting the body from harmful compounds
ð Iron-sulfur proteins
- Redox enzymes (electron transfer): xanthine oxidase (purine degradation) – succinate
dehydrogenase (TCA cycle)
- Non-redox enzymes (no electron transfer, no oxidation of reduction): aconitase (TCA
cycle)
3
, Iron food sources
- Heme iron (higher bioavailability, absorbs more directly): animal foods (lamb, beef,
salmon, chicken, tuna, sardines, eggs)
- Non-heme iron: plant foods (tofu, oats, cereals, chickpeas, nuts, brown rice, raw spinach)
Iron absorption
ð Bioavailability of a nutrient: the proportion of that nutrient ingested from a particular food or
meal that can be absorbed and is available for utilization by the body of normal metabolic
function
ð Iron is absorbed by the enterocytes of mainly the duodenum and the upper part of the jejunum
ð Different absorption mechanisms for non-heme
and heme iron)
- Non-heme iron: reduction from ferric iron
(Fe3+) to ferrous iron (Fe2+) by ferrous
reductase enzyme (ferrireductase) -> Fe2+
absorbed via divalent metal transporter 1
(DMT-1, located on membrane of enterocytes)
- Heme iron: own transport system via heme
carrier protein 1 (HCP-1, protein on
membrane of enterocytes) -> heme iron
further broken down into Fe2+ and bilirubin
(byproduct) by hemoxygenase 1 (Hox1)
o Fe2+ stored as ferritin or transported out
of enterocytes into blood via ferroportin where it binds to transferrin for distribution
ð Iron in enterocyte can follow 2 possible pathways
- Iron abundance status (sufficient iron in the body): iron will bound to ferritin and remain in
the cell -> will disappear together with the enterocyte after a few days and end up in the
stool
- Iron limiting state (varying degrees of iron deficiency): iron will be transferred from the
enterocyte to the blood via a specific transport protein (ferroportin – located in the
membrane) -> during transport Fe2+ is converted to Fe3+ by enzyme hephaestin
(ferroxidase) -> in the blood it will bind to transferring and be transported throughout the
body
ð Iron absorption in the intestine
- Average absorption non-heme iron: 5-15%
o Promote absorption: vit C (vegetables and fruits), MFP factor (meat, fish)
o Counteract with absorption: polyphenols, phytates, oxalates (chelation: formation
of an insoluble complex with iron -> no longer bind to DMT-1 receptor) – Cu2, Zn2,
Mg2, Ca2 (competition)
- Average absorption heme iron: 20-30%
o Counteract with absorption: calcium
ð On average 10% of dietary iron is absorbed
- Typical diet: 10-20mg of iron
- Small portion is absorbed: 1-2mg
o Depending on factors like dietary composition, iron status and physiological needs
4
