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for those who missed my @aberdeen_ucu talk today on #sugar, #breakfast, #health & #appetite, a wee thread on the fascinating properties of sugar...
full talk (poor sound qual) can be found here:
1/21
full talk (poor sound qual) can be found here:
1/21
#sugar is demonised in the media, literally described as "evil". myths include: its addictive, causes cravings, makes you hungry, makes you overeat, makes you gain weight.
current #publichealth guidelines target reducing sugar
2/21
current #publichealth guidelines target reducing sugar
2/21
#breakfast is touted the "most important" meal of the day. what does "important" mean?
breakfast is the highest #sugar meal of the day so a good meal to target to reduce total sugar.
breakfast = complex to define, but broadly breaks the overnight fast (break-fast) 3/21
breakfast is the highest #sugar meal of the day so a good meal to target to reduce total sugar.
breakfast = complex to define, but broadly breaks the overnight fast (break-fast) 3/21
your body has circadian rhythms, most obvious = sleep/wake cycle. cells/organs also have circadian rhythms. related to sugar, (biological) morning ingestion of sugar gives a quicker and lower #bloodsugar response, and a quicker #insulin response https://www.pnas.org/content/112/17/E2225 4/21
this means #sugar is being cleared from the blood quicker, i.e. insulin is more efficient at getting glucose out of circulation and into cells. this is good.
so if we are going to eat sugar, probably eating it in the morning is least detrimental to #health 5/21
so if we are going to eat sugar, probably eating it in the morning is least detrimental to #health 5/21
sweet taste receptors may also have a circadian (diurnal) rhythm = taste sweetness more intensely in the morning vs evening. so any #health or #appetite effects (good or bad) of sweet taste might be amplified in the morning
https://pubmed.ncbi.nlm.nih.gov/18633111/ 5/21
https://pubmed.ncbi.nlm.nih.gov/18633111/ 5/21
when you taste sweetness, you get a cephalic phase #insulin response; basal insulin can double (for ~10 min), helping to mitigate post-ingestive high #bloodsugar
https://pubmed.ncbi.nlm.nih.gov/6364839/
early insulin responses = healthier blood sugar regulation
https://pubmed.ncbi.nlm.nih.gov/11063282/ 6/21
https://pubmed.ncbi.nlm.nih.gov/6364839/
early insulin responses = healthier blood sugar regulation
https://pubmed.ncbi.nlm.nih.gov/11063282/ 6/21
contrary to media rhetoric, #insulin is a satiety hormone
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2777281/
stronger glucose/insulin responses = greater (acute) satiety
https://pubmed.ncbi.nlm.nih.gov/11477506/
https://pubmed.ncbi.nlm.nih.gov/12399274/
so maybe: morning = ↑ sweet taste = ↑ insulin = ↑ satiety? 7/21
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2777281/
stronger glucose/insulin responses = greater (acute) satiety
https://pubmed.ncbi.nlm.nih.gov/11477506/
https://pubmed.ncbi.nlm.nih.gov/12399274/
so maybe: morning = ↑ sweet taste = ↑ insulin = ↑ satiety? 7/21
sweet taste receptors are found in many cells across the body.
in the brain, they help regulate appetite, and this gets disrupted with #obesity
https://pubmed.ncbi.nlm.nih.gov/27388805/ 8/21
in the brain, they help regulate appetite, and this gets disrupted with #obesity
https://pubmed.ncbi.nlm.nih.gov/27388805/ 8/21
in the gut, sweet taste receptors are found on L cells which secrete GLP-1 when stimulated
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221019/
GLP-1 is a satiety hormone (makes you feel full), an incretin hormone (stimulates insulin), and reduces food reward (so you don't *want* to eat more) 9/21
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221019/
GLP-1 is a satiety hormone (makes you feel full), an incretin hormone (stimulates insulin), and reduces food reward (so you don't *want* to eat more) 9/21
in the pancreas, sweet taste receptors aid in #insulin secretion
https://pubmed.ncbi.nlm.nih.gov/19352508/
and stimulation of these receptors may help prevent pancreatic beta cell (the cells that produce insulin) death
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221019/ 10/21
https://pubmed.ncbi.nlm.nih.gov/19352508/
and stimulation of these receptors may help prevent pancreatic beta cell (the cells that produce insulin) death
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3221019/ 10/21
therefore, having some sugar likely helps overall in pancreatic health, appropriate #insulin secretion, and feeling full. these effects *might* be even stronger in the morning but that's quite an inference at this stage. 11/21
the idea that #sugar makes your #bloodsugar spike and crash is also worth debunking. figure 2 (in link) shows what happens when we feed 75 g of pure liquid glucose within 5 minutes to participants after an overnight fast (i.e. empty stomach):
https://journals.physiology.org/doi/full/10.1152/japplphysiol.00771.2018 12/21
https://journals.physiology.org/doi/full/10.1152/japplphysiol.00771.2018 12/21
this is over a 2 h time period - no rapid spike, no crash. insulin & glucose show a well controlled homeostatic response
to put this in context: 2 cans of coke = ~75 g sugar. ~50 % of this sugar is #fructose (doesnt effect #bloodsugar). 13/21
to put this in context: 2 cans of coke = ~75 g sugar. ~50 % of this sugar is #fructose (doesnt effect #bloodsugar). 13/21
so to get ~75 g GLUCOSE = ~4 cans of coke
in a breakfast context - of 101 UK breakfast cereals i looked at, @KelloggCompany Frosties had the highest #sugar (37 % by weight). if you had a large portion (50 g) + 250 mL semi skimmed milk = ~30 g sugar 14/21
in a breakfast context - of 101 UK breakfast cereals i looked at, @KelloggCompany Frosties had the highest #sugar (37 % by weight). if you had a large portion (50 g) + 250 mL semi skimmed milk = ~30 g sugar 14/21
(total carbohydrates = ~56 g). still nowhere near the 75 g glucose.
also consider:
1. ~half the sugar will be fructose = doesn't affect your #bloodsugar
2. the sugars are in a food matrix = slower digestion, some won't get absorbed, etc 15/21
also consider:
1. ~half the sugar will be fructose = doesn't affect your #bloodsugar
2. the sugars are in a food matrix = slower digestion, some won't get absorbed, etc 15/21
so it would be surprising if your large sugary cereal gave you a rapid spike and crash when we can't even achieve that with 75 g pure liquid glucose
(in healthy adults) 16/21
(in healthy adults) 16/21
considering this, it's unsurprising that:
1. #carbohydrate and #sugar are inversely associated with #obesity
https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1467-789X.2008.00565.x
2. when people cut out sugar and lose #weight, they have just cut total calories (ie. nothing magic about sugar)
https://www.bmj.com/content/346/bmj.e7492 17/21
1. #carbohydrate and #sugar are inversely associated with #obesity
https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1467-789X.2008.00565.x
2. when people cut out sugar and lose #weight, they have just cut total calories (ie. nothing magic about sugar)
https://www.bmj.com/content/346/bmj.e7492 17/21
3. there's no associated between #carbs, #sugar, #insulin resistance, and #diabetes
https://pubmed.ncbi.nlm.nih.gov/19207533/
to top it off, my research showed 3 wk plain vs sweet (same calorie, 30 % by weight sugar) #breakfast had NO DIFFERENCE in:
https://onlinelibrary.wiley.com/doi/full/10.1002/oby.22757
18/21
https://pubmed.ncbi.nlm.nih.gov/19207533/
to top it off, my research showed 3 wk plain vs sweet (same calorie, 30 % by weight sugar) #breakfast had NO DIFFERENCE in:
https://onlinelibrary.wiley.com/doi/full/10.1002/oby.22757
18/21
body massenergy intakephysical activityfasted biomarkers of health (glucose, TAG etc)fasted appetite hormones (GLP-1, FGF21)psychological approach to foodcravingsliking of plain or sweet porridge*post-breakfast sugar intake*19/21
we did find:
after sweet breakfast a REDUCTION for sweet desire (back to baseline levels by lunch (as predicted by sensory specific satiety)
20/21
after sweet breakfast a REDUCTION for sweet desire (back to baseline levels by lunch (as predicted by sensory specific satiety)20/21
overall, my take on all this is that if you enjoy #sugar then moderate consumption is ay okay in healthy adults.
if you need to lose weight, targeting any nutrient or meal can do the trick; for some this might be cutting #breakfast or #sugar 21/21
if you need to lose weight, targeting any nutrient or meal can do the trick; for some this might be cutting #breakfast or #sugar 21/21
PS. thanks to everyone who attended today, hope you found it interesting. next talk is in 2 week on #hydration and i shall debut the new theory i've been working on!
