Sodium and Potassium Overview

These flashcards cover key concepts, health impacts, dietary sources, recommendations, and public health strategies related to sodium and potassium.

What is the role of sodium in the body?

Sodium is an essential element that ( with potassium and other electrolytes) provides electrolyte balance through ‘active transport’ across cell membranes.

• balances fluid + proper ph in the body

• carries electrical signals from nerves to muscles

What are the health risks associated with increased sodium intake?

Increased sodium intake is linked to:

• Higher blood pressure > raises the risk of cardiovascular events, chronic kidney disease, stomach cancer, and osteoporosis.

What are the major dietary sources of sodium for New Zealand adults?

Major sources include bread, bread-based dishes, grains, pork, and processed meats.

What is the recommended dietary sodium intake for adults?

Adults should reduce sodium intake to less than 2000mg/day (5g salt).

What are the health benefits of potassium intake?

Increased potassium intake is associated with lower blood pressure and reduced risk of cardiovascular disease.

What are the major dietary sources of potassium for New Zealand adults?

Major sources include potatoes, kumara, vegetables, fruit, and milk.

What is the relationship between potassium and sodium regarding blood pressure?

High potassium intake helps the body reduce sodium retention, leading to lower blood pressure.

What strategies have been implemented in New Zealand to reduce sodium intake?

Strategies include voluntary targets set by the Heart Foundation and promoting the Health Star Rating for packaged foods.

What is the WHO's sodium intake reduction target for populations?

The WHO aims to reduce sodium intake by 30% in populations by 2025.

Why is measuring sodium intake important for public health?

Understanding sodium intake is crucial for developing effective nutrition interventions and reducing associated health risks.

1g of salt (NaCl) is how many mg of sodium and chloride?

400mg Na, 600mg Cl

What are the main uses of salt/sodium?

Preservative, binder, stabiliser, flavour enhancer; ice and snow removal, water conditioning, industrial chemicals

What is the primary role of sodium in the body?

Sodium is an essential element that, along with potassium and other electrolytes, provides electrolyte balance between the inside and outside of cells through 'active transport'

• fluid balance, balance body ph, PNS connection to muscles

What is the primary health consequence of increased sodium intake?

Increased sodium intake > increased blood pressure (BP) > increased risk of cardiovascular events (CVD).

List the six mechanisms by which sodium affects blood pressure.

• water retention

• increased resistance of the arteries to blood flow

• alterations in cell functioning

• changes in artery structure and function (becomes stiff)

• modifies heart activity

• modifies the automatic neuronal system in the cardiovascular system

what three other health conditions (NOT CVD) are independently associated with high salt intake?

Kidney disease, stomach cancer, osteoporosis.

How does sodium intake affect water retention in the body?

-additional water rentetion > more stress on arteries > elevated blood pressure

How does sodium affect arterial function?

Sodium increases resistance of the arteries to blood flow and causes changes in artery structure and function, particularly increasing arterial stiffness.

restricted blood flow/ increased stress on arteries > high BP

what neurological effects does high sodium intake have on the cardiovascular system?

modifies the autonomic neuronal system (reflexes, nerve messages to muscles) in the cardiovascular system, contributing to increased blood pressure.

Why is urinary sodium excretion a good measure of how much Na we consume?

Because we excrete majoity of the Na we consume > the more we excrete, the more we are consuming

What does the INTERSALT study (52 countries, 10,000+ adults) tell us about sodium and age?

Higher levels of urinary Sodium excretion (g per day) are positively correlated with systolic blood pressure levels across age groups.

Higher sodium consumption (measured through excretion) increases systolic blood pressure with age.

What did the INTERSALT study find about sodium reduction and blood pressure?

A linear relationship exists between reduction in urinary sodium excretion and reduction in systolic blood pressure.

OR

a dose-response relationship between reduction in urinary sodium excretion and reduction in systolic blood pressure.

What explains the J-shaped curve found in some cohort studies on sodium intake and health outcomes?

The J-shaped curve is likely due to biased estimation of salt intake (e.g., from spot urines) and reverse causality.

• evidence behind these studies is not based on good dietary intake data, or gold standard 24-hour urine collections for sodium intake.

What are the major dietary sources for sodium for New Zealand adults from the 2008/9 ANS?

Bread (18%), bread-based dishes (11%), grains and pasta (7%), pork (7%), sausages and processed meats(5%)

• There were also differences between groups, e.g females (soups and stocks), Pacific communities (poultry) and Māori (pork).

What was the conclusion when experts examined the evidence regarding salt intake and public health (minus J-shaped curve)'?’

"Even a modest reduction in salt intake across the whole population will lead to a major improvement in public health, along with huge cost-savings to the healthcare service."

According to the discretionary salt intake study conducted in Dunedin, what percentage of salt consumed was discretionary?

13% of salt consumed was discretionary (added during cooking or at table)

why is it important to know how much (or little) salt is coming from discrentionary intake?

indicates that the majority of salt (87%) comes from sources other than salt added during cooking or at the table, suggesting that public health interventions targeting processed foods would be more effective than focusing solely on discretionary salt use.

List the top five sodium sources for New Zealand adults from the 2008/09 Adult Nutrition Survey.

1) Bread (18%),

2) Bread-based dishes (11%),

3) Grains and pasta (7%),

4) Pork (7%),

5) Sausages and processed meats (5%).

what demographic differences exist in sodium sources among New Zealand population groups?

demographic groups showed different major sources: females consumed more sodium from soups and stocks, Pacific communities from poultry, and Māori whānau from pork.

Why is it important to know the major dietary sources for sodium (in NZ adults) in terms fo public health?

so we know where sodium is coming from, for different groups + demographics

What is the WHO sodium intake recommendation for adults?

<2,000 mg/day (equivalent to 5 g salt or 1 teaspoon).

Do WHO sodium recommendations apply to adults with normal blood pressure?

they apply to all adults, regardless of blood pressure.

According to WHO, how should sodium intake be adjusted for children?

<2,000 mg/day based on energy requirements.

What is the AI (Adequate Intake) range for sodium in NZ & Australian NRVs for adults?

460 to 920 mg/day.

This range is set to ensure sufficient sodium intake for adults while preventing deficiencies.

What is the SDT (Suggested Dietary Target) for sodium in NZ/Australia?

<2,000 mg/day (equivalent to 5 g salt or 1 teaspoon).

What is the AI range for sodium intake in children according to NZ & Australian NRVs?

200 to 920 mg/day, depending on age.

What is the UL (Upper Limit) for sodium intake for AUS/NZ children?

1,000 to 2,300 mg/day, depending on age.

What is the gold standard method for measuring sodium intake?

24-hour urine collections

What was the average sodium intake in the 2011 NZ urine study?

3,459 mg/day.

What is the WHO's global salt intake reduction target for 2025?

30% population reduction in salt intake

Name one strategy NZ uses to reduce sodium at the population level.

Voluntary Heart Foundation sodium reformulation targets for packaged foods.

What was the average sodium intake in a 2012 study?

3,386mg a day

What is the average sodium intake of New Zealand adults based on 24-hour urine studies?

3,386mg a day (3000-3,500mg)

• men are higher than women (bc they eat more)

• no good data on income, ethnicity

• no apparent reduction over time

What percentage of New Zealand adults exceed the Upper Limit (UL) for sodium intake?

3/4’s or 77%

how much sodium do New Zealand children consume on average?

Mean intake is approximately 2,191 mg sodium per day

with a range of 1087-4786 mg.

If data shows no noticeable difference in sodium intake between income/ethnicity, why is public health still concerned about discrepancies between group intake?

Beacues while existing data suggest no noticeable difference, much more credible and reliable data shows significant differences in blood pressure and CVD.

the data we have is okay at best, we need better more relevant and new data. Our data is okay at best; we need gold standard data though as what is there likely is not longer the case.

What % of adults are sufficiently adding salt to food (MOH ANS, 2008/9)?

50% (sometimes >regularly > always), though outdated

Pilot study by Eyles et al (2018) on sodium intake for NZ children found….

sodium intakes were >WHO guidelines

• mean 2191mg a day, with range 1087-4786mg

• sources: bread, pies, pastries, pasta-based dishes

• important to remember these kids have less caloric intake than adults > higher concentrations of sodium in processed foods

What other methods can be used to assess sodium intake?

• Spot urine samples

• dietary assessment techniques (diet recall, record, or FFQ)

• dietary habits questions

• food purchasing data and food balance data.

Knowledge, Attitudes, behaviours on dietary salt in nz study:

RECRUITMENT + SAMPLE SIZE + DEMOGRAPHIC

Recruitment: Shopping malls and Facebook.

N= 843 NZ adults (81% female), surveyed in 2018 using a cross-sectional design.

What percentage of participants believed New Zealanders eat too much salt?

91%

How many NZers knew the link between salt and sodium?

62%

What percentage of NZers knew processed foods = main source of salt?

87%

Sodium knowledge, attitudes, and behaviors in New Zealand

• 91% knew ate too much

• 62% knew relationship between salt-sodium

• 87% knew sodium main source proocessed foods

Sodium knowledge, attitudes, and behaviors in New Zealand

• 32% believed their health would improve with less salt

• 57% supported laws to limit salt in processed foods

• 90% said individual’s fault

• 83% said the food industry’s fault

Sodium knowledge, attitudes, and behaviours in New Zealand

61% avoided eating packaged foods

53% added salt during cooking

18% added salt at the table

Who did participants think were responsible for salt intake?

90% said individuals; 83% said the food industry.

What are the five activities recommended by WHO for sodium reduction?

(SHAKE)

S H A K E :

1) Surveillance (monitor and measure salt use)

2) Harness industry (reformulation)

3) Adopt standards for labeling and marketing

4) Knowledge (education and empowerment)

5) Environment (support settings).

What was the UK's three-pronged approach to national salt reduction?

Public awareness campaign, food labeling changes, and manufacturer targets.

How much did urinary salt excretion in adults in England decrease in the first seven years of their program?

Approximately 15%, from 9.5 g to 8.1 g.

WHO UN NCD Target to reduce population salt intakes: when and how?

6 targets led by NHF aiming for:

30% relative reduction in population salt intake by 2025, NZ did sign up for this

has nz met 30% relative reduction in population salt intake by 2025 ?

no, not a 30% reduction by 2025. NZ signed up, but has made no strategies at all.

what does SHAKE mean?

who’s best practice for reduced sodium instake = S H A K E :

1) Surveillance (monitor and measure salt use)

2) Harness industry (reformulation)

3) Adopt standards for labeling and marketing

4) Knowledge (education and empowerment)

5) Environment (support settings).

Sausages in NZ (sodium):

7x times more salt than similar products, at times ½ the daily sodium intake in a single sausage

UK salt reduction campaign (2003-ongoing) has three prongs… what are they?

public awareness campaign

food labelling changes

manufacturer targets

UK 2017 prgress on manufacturing targets…. what were they?

52% of overall salt targets were met by manufacturers + retailers

81% of packaged products were either AT or BELOW max target

71% BELOW max targets

New Zealand's two main strategies for sodium reduction?

1) voluntary targets developed and left by the Heart Foundation in collaboration with industry

2) Voluntary Health Star Rating front-of-pack nutrition label (sodium is a contributor here, not the main target)

percentage of packaged foods in NZ with health star rating (2024)

33%

Are NZ ‘s two main strategies set by the HF enough for the promised WHO 30% reduction by 2025?

No.

In NZ, the daily sodium intake (3000-3500mg) is one of the two main strategies set by the Heart Foundation to reduce sodium intake (potentially) by 260mg. very short of the target.

30% of even the low range of average sodium intake (3000mg) would need to be reduced by 900 mg.

What was NZ’s score in WHO’S 2023 global report on sodium intake reduction check?

2/4

What is the role of potassium in the body?

Also another essential element/electrolyte:

• important for fluid and electrolyte balance.

• PH balance in body fluids.

• It helps lower blood pressure when intake is higher.

Why does postassium (K) work with sodium? is there a ratio?

What sodium increases, potassium decreases. 1:1 ratio.

Where is Pottassium found? Where could I eat more of it?

cells of unprocessed foods- fruit, vege, legumes, wholegrans, milk, meat

What are the major dietary sources of potassium for New Zealand adults?

Potatoes, kumara, taro (13%), vegetables (12%), non-alcoholic beverages (10%), milk (10%), and fruit (10%).

What are the major dietary sources of potassium for New Zealand children?

Potatoes, kumara and taro (19%), milk (15%), fruit (11%), vegetables (7%), and bread (6%).

How is increased potassium intake related to blood pressure and cardiovascular disease (CVD)?

It is associated with lower blood pressure (BP) and a lower risk of CVD.

What does a high potassium diet signal the body to do?

It signals the body to reduce sodium retention, which helps lower blood pressure.

2021 study concluding:

+1000 mg sodium = 18% increase of CVD risk;

+1000 mg Potassium = 18% decrease in risk of CVD

does the median NZ Potassium intake met AI for potassium? (moh ANS 2008/9)

No

• men are under their 3800mg AI for potassium

• women are under their 2800mg AI for potassium

What is WHO’s AI for potassium?

3510mg

what is the gold-standard collection for potassium?

like sodium, 24 hour urine collections and 24 hour diet recalls

What was the mean and range of potassium intakes for NZ children?

Mean= 1776mg potassium per day (low in reference to sodium and suggested intake)

range 800-2981mg a day

How do you achieve a high-potassium diet?

• eat lots of wholefoods, reduce processed foods

• high in fruit + beg, low in butter, red meat and high fat foods

• e.g the DASH diet, mediterranean style diets

public health appraoches for high-potassium diets…..

• remove gst from fruit + vege

• vouchers for fruit + vege

• community cooking programmes

• salt replacers also increase potassium intakes

How do Salt replacers help?

• adresses discretionary salt and salt in packaegd foods

• less sodium, has potassium in the salt (iodised salt)

• is kcl not nacl

What percentage of sodium is estimated to come from discretionary salt intake (adding to food)?

13%

How much sodium is in 1g of salt?

400mg, the rest is 600mg cl

What is the World Health Organisation recommendation for sodium intake per day for adults?

<2000mg a day

What is the estimated daily salt intake of New Zealanders?

What is the best way to measure sodium intake?

24 hour urine collections

What is the major source of sodium in the New Zealand diet?

bread is no.1

Why is high salt intake of concern?

increased bp> increased risk CVD

What is a major role of potassium?

lowers BP

Why are some New Zealanders low in potassium?

do not eat enough vegetables

What is a major function of sodium?

balance bodily fluids, transmit nerve impulses, muscle contraction

How does the mean sodium intake of New Zealanders (2011 data) compare to the WHO guidelines?

above WHO guidelines

Globally, where does diets high in sodium rank in number of deaths compared to other dietary risk factors?

second highest