January Flashcards
Minerals and Food Labelling (184 cards)
1
Q
What are minerals?
A
Inorganic elements that originate in the earth and cannot be made by living organism
2
Q
What must minerals be attached to for humans to be able to absorb it?
A
organic compounds, containing carbon (these are then removed so the mineral can be utilised by the body)
3
Q
how much of our body weight is minerals?
A
4-5%
4
Q
What two minerals make up the most of the minerals in our bodies?
A
Calcium and phosphorus
5
Q
What are the seven macrominerals?
A
Calcium, phosphorus, magnesium, potassium, sodium, chloride, sulphur
6
Q
What are the 11 trace minerals?
A
iron, zinc, iodine, selenium, manganese, molybdenum, copper, chromium, boron, fluoride, silicon
7
Q
What minerals exist as cations?
A
positively charged: potassium, magnesium, calcium, sodium
8
Q
What minerals exist as anions?
A
negatively charged: chloride, sulphate, phosphate
9
Q
What factors affect mineral bioavailability?
A
- mineral status in the body (if low minerals, the body makes more transport proteins)
- substances present in foods (ascorbic acid, phytates can enhance or inhibit absorption)
- other minerals present in foods (they can compete)
10
Q
Which metals commonly compete for absorption?
A
Zn and Fe, Zn and Cu
11
Q
What is a ligand?
A
A molecule that binds to another molecule
12
Q
What are some common mineral carriers used in supplements?
A
Organic: citrate, ascorbate, gluconate, glycinate
Inorganic: oxide, carbonate, sulphide, chloride
13
Q
What mineral is the most abundant in the body?
A
Calcium
14
Q
What are the functions of calcium?
A
- building and preserving bone mass
- synapses
- cardiac muscle function and vasoconstriction
- used for binding of actin and myosin
- needed to activate vitamin-dependent clotting factors
- required for conversion of tryptophan to serotonin
15
Q
What regulates calcium levels?
A
Parathyroid hormone (increases serum Ca)
Vitamin D (increases serum Ca)
Calcitonin (lowers serum Ca, puts it in the bones)
16
Q
What food sources are high in calcium?
A
dark and cruciferous veg, nuts and seeds, beans, dairy, herbs
17
Q
How does the bioavailability of calcium in veg and dairy differ?
A
Calcium in veg is absorbed 2x as efficently
18
Q
Where is calcium mostly absorbed?
A
In the duodenum
19
Q
How does vitamin D affect calcium absorption?
A
Vit D (calcitriol), binds to enterocytes and increases calcium transporters
20
Q
What factors decrease calcium absorption?
A
- low vitamin D
- low stomach acid
- high phytates and oxalates
- GI dysfunction
- other minerals competing (Mg, Fe, Zn)
21
Q
What factors increase calcium excretion?
A
- menopause (low oestrogen)
- high animal protein diets (high urea, and sulphuric acid)
- high salt
- high caffeine
22
Q
What are the disadvantages of using cows milk as a source of calcium
A
It is high in sulphur-based amino acids that cause calcium to be leached from the bones
23
Q
What are natural ways of increasing calcium?
A
Optimise vit D and K levels
increase plant-based calcium rich foods
24
Q
What is the maximum amount of calcium absorbed in one sitting?
A
500mg
25
What are the negatives of calcium supplementation?
it can increase risk of kidney stones, soft tissue calcification
26
Which minerals does calcium interfere with the absorption of?
Mg, Fe, Zn, P
27
What foods are high in magnesium?
Leafy greens, nuts and seeds, beans, whole grains, cacao powder
28
What are the functions of magnesium?
- converting ADP to ATP
- needed for glucose metabolism - role in insulin sensitivity
- ion transport and conduction of nerve impulses
- Mg inhibits blood clotting
- helps making tooth enamel
- breaks actin-myosin bonds
- cofactor for GABA and serotonin-melatonin (sleep)
29
Where is magnesium absorbed?
In the Ileum
30
What foods inhibit magnesium absorption?
high-phytate foods and calcium
31
Why are serum magnesium levels not accurate?
Most magnesium is stored in the cells and blood concentration does not affect this
32
Which form of magnesium is best for constipation?
Magnesium citrate
33
What is the tolerable upper limit of magnesium supplements?
400mg (can cause diarrhoea in high amounts)
34
What form of magnesium is in epsom salts?
Magnesium sulphate
35
What condition should you use magnesium with caution?
hypotension
36
What are the symptoms of magnesium insufficiency?
fatigue, insomnia, anxiety, depression, hypertension, muscle cramps, headaches, palpitations
37
What key reactions is zinc a cofactor for?
Antioxidant (superoxide dismutase), alcohol dehydrogenase, digestion of proteins, haem synthesis, folate absorption, DNA synthesis
38
What food sources are high in zinc?
oysters, nuts and seeds (sesame), grains (rye), calf's liver, legumes (chickpeas)
39
What are the key functions of zinc?
- production of sex hormones, spermatogenesis and prostatic fluids
- inhibits 5-alpha reductase
- needed for T4-T3 conversion
- Needed for cell proliferation (skin)
- Senses
- antioxidant, anti-inflammatory, anti-viral
- needed for production of HCl, and pancreatic enzymes
40
What food aids zinc absorption?
Proteins
41
What foods can reduce zinc absorption?
Foods high in phytates (legumes, whole grains, nuts and seeds - that have not been soaked)
42
What are the signs and symptoms of zinc deficiency?
poor sense of taste and smell, recurrent infections, skin disorders, low libido, signs of weak digestion
43
What is the supplemental range for zinc?
15-25mg a day - with food
44
What is the tolerable upper limit for Zinc?
40mg - long term
45
Where is most phosphorus stored in the body?
As hydroxyapatite in the bones and teeth
46
What are the negatives of high phosphoric acid?
it can cause calcium to leach from the bones
47
What are the functions of ATP?
- part of ATP, bones, teeth, DNA
- creatine phosphate is a storage unit of energy in muscles
- phospholipids in cell membranes
48
What are the effects of high phosphates?
hyperactivity in children
49
What foods are high in phosphorus?
carbonated drinks, processed food, fast food
50
What food sources are high in potassium?
raw spinach, potato skins, avocado, quinoa, pistachio, clams, calf's liver
51
What are the key functions of potassium?
- nerve transmission, muscle function
- cofactor for energy metabolism, glycogenesis, cellular growth and division
52
What is the amount of potatssum required daily?
2g
53
What are common causes of potassium deficiency?
Diuretics, diarrhoea, vomiting, laxative abuse, chronic renal disease
54
What are the symptoms of low potassium?
- muscle cramps/weakness
- hypertension
- confusion
- thirst
- insomnia
55
What are the signs of chronic potassium toxicity?
cardiac irregularities, paralysis of extremities, confusion, tingling, weakness, kidney failure
56
What are three general functions of minerals in the body?
to build tissues, to maintain nerve and muscle function, to make thyroid hormones
57
Which mineral competes with zinc for absorption?
Copper
58
What is table salt made from?
40% sodium, 60% chloride by weight
59
What are the bad things about table salt?
- it is heat treated and bleached and anti-caking agents like aluminium are added
- It has no nutritional value
60
What are the pros and cons of sea salt?
- unprocessed so has a high mineral content
- may contain heavy metals and impurities
61
What are the benefits of himalayan sea salt?
It contains 84 trace minerals in a good ratio
the trace minerals have therapeutic benefits
62
What are the benefits of grey/celtic salt?
It has a similar nutritional profile to Himalayan salt, high in minerals and moisture
63
What hormones increase sodium levels in the body?
Renin, Aldosterone (increases sodium reabsorption and absorption)
64
Which hormone lowers sodium levels?
ADH
65
What is the minimum requirement of salt?
500mg
66
What is the best way to reduce sodium intake?
eating whole foods
67
What are the key functions of NaCl?
- Maintaining acid-alkaline balance
- nerve impulse transmission
- controls muscle contractions
- part of HCl
68
What are the causes of NaCl deficiency?
- persistent diarrhoea
- overuse of diuretics
- vomiting
- anorexia
- major trauma
69
Which people are more sensitive high salt intake?
- CKD
- Diabetes mellitus
- obese people
- those over 50yrs
- those of african origin
70
How much iron is there in the body?
3-4g
71
What two forms of iron exist in the body?
ferrous (Fe2+) and ferric (Fe3+) iron
72
What are the two types of iron in food?
- non-haem iron: Fe3+ plants and animals
- haem iron: Fe2+ only animals
73
What foods are high in iron?
- quinoa, amaranth, soybeans, spinach, pumpkin, clams
74
What are the functions of iron?
- part of haemoglobin (4 iron molecules per haemoglobin)
- part of myoglobin
- part of the cytochrome enzymes in the electron transport chain
- thyroid peroxidase to make thyroid hormones
- lymphocytes
- making dopamine
75
How is excess iron stored?
as haemosiderin
76
How is excess iron excreted?
It cannot be excreted, and is only lost through bleeding
77
What is the function of ferritin?
it takes iron from food and stores it in the small intestine mucosal cells
78
What is the function of transferrin?
It transfers iron around the blood to tissues
79
What enhances the absorption of iron?
vitamin C
80
What is the difference in absorption of haem and non-haem iron?
haem (15-35%) has a higher absorption rate than non-haem iron (2-20%)
81
What form of iron is usually given in supplements by GPs?
ferrous sulphate
82
What substances decrease iron absorption?
Phytates, oxalates, polyphenols, calcium and phosphorus, tannic acid
83
What are the symptoms of iron deficiency anaemia?
fatigue on exertion, weakness, headaches, apathy, breathlessness, nail spooning, hair loss
84
Who are at risk of iron overload?
men, those consuming high levels of haem iron (meat), as absorption of these cannot be downregulated. haemochromatosis, high dose vit-C supplementations
85
Why is iron overload bad?
- iron is a pro-oxidant
- It is a bacterial growth factor so can increase infection rates
- it can accumulate in the brain and liver
86
Which other minerals compete with iron absorption?
Zinc, copper, calcium
87
Which antioxidant is selenium part of?
glutathione peroxidase
88
Why is mercury bad for you?
it occupies the active site of glutathione peroxidase
89
Name some high selenium food sources
whole wheats, Brazil nuts (from Brazil), sunflower seeds, yellowfin tuna, garlic, calf's liver
90
What are the functions of selenium?
- co-factor in glutathione peroxidase
- T-lymphocyte proliferation, and antibody production
- conversion of T4 to T3
- sperm motility
91
Where is selenium absorbed?
In the duodenum
92
What are the signs and symptoms of selenium deficiency?
- high T4-T3
- 'keshan disease' - cardiomyopathy in areas with low selenium in soil
93
What are the toxicity signs of selenium?
brittle hair and nails, skin problems, depression, garlic odour
94
What is the tolerable upper limit for selenium?
300ug
95
What are the key food sources of copper?
- sesame seeds, cashews, quinoa, shiitake, calf's liver, oysters
96
What are the functions of copper?
- it is part of the antioxidant enzymes superoxide dismutase and ceruloplasmin
- supports skin and blood vessel structure and melanin
- it is involved in making RBCs
- phagocytes use copper to kill bacteria
- used for making the myelin sheath
- used to make noradrenaline
97
What are common causes of copper deficiency?
long term zinc supplementation
cow's milk
98
What are the common signs of copper deficiency?
- anaemia
- bone fractures (due to copper's role in collagen structure)
- impaired growth, reduced skin pigment
- recurrent infections
99
What are the signs of copper toxicity?
- vomiting, diarrhoea, liver/kidney damage, coma, wilson's disease signs
100
What can cause copper overload?
Zinc deficiency, wilson's disease,
101
What are good food sources of iodine?
- sea vegetables, ocean fish and shellfish
102
What are the functions of iodine?
- essential part of thyroid hormones
- foetal and infant brain and bone development
- cell metabolism
103
Which thyroid hormone is the active one?
T3 (triiodothyronine)
104
What are the signs of iodine deficiency?
hypothyroidism - weight gain, depression, fatigue, goitre
105
How much iodine should you have a day?
150mcg
106
Which foods have goitrogenic effects?
Brassica vegetables (only when low iodine and if you have lots of them)
107
What are some key food sources of manganese?
wheat germ, rye, hazelnuts, cloves, saffron, blue mussels
108
What are the functions of manganese?
- helps make enzymes involved in gluconeogenesis
- needed to make proteoglycans in cartilage and collagen
- antioxidant - cofactor in superoxide dismutase
109
What are the signs of manganese insufficiency?
- manganese for creaky knees
- hair greying, skin rashes, bone and tendon issues
110
Which minerals can interfere with manganese absorption?
Fe, Ca, Mg
111
What are the common food sources of chromium?
broccoli, barley, turkey, black pepper
112
What are the functions of chromium?
It improves insulin resistance by increasing tyrosine kinase sensitivity
113
What are the signs of chromium deficiency?
poor blood sugar control - anxiety, sugar cravings
114
What can cause low chromium?
- high carbs
- vigorous exercise
115
What key molecules contain suphur?
- Acetyl CoA
- Biotin
- Thiamine
- Glutathione
116
What foods are high in sulphur?
- alliums
- cruciferous veg
- soya beans
- eggs and dairy
- meats
117
What are the functions of sulphur?
- antioxidant (used to make glutathione)
- needed to produce insulin
- component of keratin for skin/hair
- component of collagen
- phase 2 liver detoxification
118
What enzymes is molybdenum a cofactor of?
- sulphite oxidase - detoxing sulphites
- xanthine oxidase (making uric acid from purine)
- aldehyde oxidase (drug detox)
119
What are some good food sources of molybdenum?
legumes, whole grains, nuts, leafy greens, beef liver, milk
120
What is the recommended daily intake for molybdenum?
45mcg
121
What is boron used for?
bone development
122
What is silicon used for?
bone mineralisation and connective tissue
123
What is bad about fluoride?
It is toxic to the thyroid gland
124
What effect do PPIs have on minerals?
lowers calcium iron and zinc
125
table salt restriction is a key intervention for which condition?
hypertension
126
What is the primary role of iodine in the body?
to make thyroid hormones
127
What must be included on a food label?
- name
- made-up name
- processing
- weight/volume
- preparation and storage instructions
- ingredient list
128
What is the difference between best before and use-by?
best before - quality of the food
use by - safety of food
129
What is the order of the ingredients list?
by weight, with highest weight first
130
What is mandatory to be included on the back of pack labelling?
energy (per 100g/ml)
fat + saturates
carbohydrates + sugars
protein
salt
131
What are the reference intakes based on?
an average sized woman doing an average amount of physical activity
132
What are the RIs for energy, fat, carbs and proteins?
- energy: 2000kcal/8400kJ
- fat: 70g, saturates 20g
- carbs: 260g, sugars 90g
- protein 50g, salt 6g
133
what are the 14 allergens that must be included?
gluten, eggs, fish, crustaceans, peanut, soya, celery, milk tree nuts, mustard, sesame, sulphur dioxide, lupin, molluscs
134
What alcohol percentage must be included on a label?
- above 1.2%
135
What else must be included on a food label?
- GM ingredients above 0.9%
- if a product has been irradiated
- is packaged using a gas
136
How much gluten can be in gluten free products?
20mg/kg
137
What are the issues with GMO foods?
can lead to infertility, immune issues, impaired insulin regulation and accelerated ageing
138
How much fat can a product contain to be able to put low fat on it?
less than 3g of fat per 100g or 1.5g of fat per 100ml
139
What are the 6 categories of E numbers?
- colours E100s
- Preservatives E200s
- Antioxidants E300s + E586
- Thickeners and emulsifiers E400s + E322 and E1103
- Flavour enhancers E600s
- Sweeteners E900s + E420 +E421
140
What is an artificial food additive and an example?
an additive that is made synthetically - azodicarbonamide flour improver
141
What is a nature-identical food additive?
manufactured copies of substances found naturally in foods - benzoic acid as a preservative
142
What is a natural food additive?
Substance extracted from food for use in other foods. E100 - curcumin. E162 - beetroot.
143
What are the negatives associated with artificial colours?
associated with hypersensitivity and poor concentration
144
Name 3 common preservatives
E211 sodium benzoate - fizzy drinks
E220 sulphur dioxide - dried fruit
E251 sodium nitrite - processed meat
145
What are artificial preservatives associated with?
Asthma and allergies
146
What food antioxidants are commonly used?
E310 - propyl gallate
E320 - BHA
147
What are some common emulsifiers used?
- polysorbate 80
- carboxymethyl cellulose
148
What are some issues with artificial emulsifiers?
Increases risk of IBD, colon cancer
149
What are some common stabilisers used?
lecithin, agar-agar, carrageenan, pectin
150
What is a common flavour enhancer used?
E621 - MSG
151
What are the effects of MSG?
Headaches, skin flushing, muscle tightness, dizziness, heart palpitations
152
What are some natural sweeteners?
stevia, xylitol
153
What are some synthetic sweeteners?
aspartame, saccharin
154
What effects do artificial sweeteners have on the body?
They can raise insulin levels and affect insulin sensitivity
It can over-stimulate sugar receptors and increase sugar cravings
155
What is the safest alternative to sugar?
plant- derived stevia
156
What are flavour packs?
Parts of fruits and foods are extracted and broken down into individual constituents which are then reassembled into the juice
157
What are the negatives with Carrageenan? - red seaweed
causes GI inflammation, bloating and bowel disease
158
What are the negatives of E330 - citric acid?
made from GM high fructose corn syrup - GM ingredients
159
What vitamin does chlorine dioxide deplete?
Vitamin E
160
What vitamin does sulphur dioxide deplete?
B1
It also reduces the oxygen carrying capacity of haemoglobin
161
What food additives should be avoided?
- E160b annatto natural colour
- E120 Cochineal natural colour
- E240-52 Nitrates and nitrites
- E220 sulphur dioxide preservatives
- E320 BHA antioxidants
- E321 BHT antioxidants
162
What antioxidants cannot be used in foods designed for babies and young children?
E320 BHA and E321 BHT
163
What are the negatives of ACE-K acesulfame K sweetener?
headaches, nausea, depression, carcinogenic
164
How can you reduce the amount of chemicals on fruits and veg?
wash in 2% salt solution or white distilled vinegar and water solution
165
What are the issues with using plastic packaging?
- BPA and other plastics are xenoestrogens so can mimic oestrogen in the body and disrupt normal function
166
How are foods irradiated?
using high energy electron beams, X-rays or gamma rays
167
What are the issues with irradiating foods?
benzene and formaldehyde can be produced which are carcinogenic
168
Does irradiation kill the bacteria?
Yes, it kills the majority of them, the ones left can mutate and toxins are not destroyed
169
What is the EAR?
estimated average requirement needed by a group
170
What is the RNi?
When 97.5% of the population's requirement is met
171
What is the LRNI?
lower recommended nutrient intake, only 2.5% of the population's requirement is met
172
What are the mandatory fortifications in white flour?
- calcium carbonate
- iron
- thiamine
- nicotinic acid/nicotinamide
173
What are the problems with fortification?
- it does not promote healthy eating
- uses mostly synthetic nutrients
174
Why has RI been replaced by GDA?
It was believed that guideline was a better way to show it was something to aim for
175
To be able to include a vitamin or mineral on pack, what is the minimum amount that must be in the product?
At least 15% of the NRV per 100g/ml or per serving size
176
Give some examples of nutritional databases?
cronometer, myfitness pal, nutrition database, nutritics, nutritiondata.com
177
What are the issues with using food composition tables for RNIs?
- It does not show how much of a nutrient will be absorbed
- nutrient content of foods vary
- cooking methods alter nutrient content
178
What are the three key reasons for measuring food intake?
- to evaluate the adequacy and safety of foods
- to study the relationship between food intake and physiological function
- to assist with the diagnosis and treatment of diet-related conditions
179
What are estimated dietary assessments?
When the amounts of foods are assessed by volume e.g. cups, rather than weight
180
What is general included in a dietary history?
- food eaten on a typical day
- food intake for given time period is explored
181
What are food frequency questionnaires usually used for?
estimating the amount of foods consumed containing a particular nutrient
182
As nutritionists what is the best way to assess a diet?
use a variety of tools and assess based on different clients
183
What are the most important dietary aspects to initially explore?
- start with macronutrients
- then go into micronutrients
184
What should be included in a food diary?
- all meals and snacks
- portion sizes
- all fluids
- methods of food preparation
- symptoms following meals
- triggers for eating certain foods
- time of meals
- supplements
