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27 January 2025

Leading Nutritional Scientist: Seed Oils Are Not Bad For You! Eating This Twice A Day Will Help Menopause! The Alarming Link Between Chewing & Belly Fat!

4Frameworks
13Insights

Frameworks in this episode

Insights & moments

The myth-busts, hot takes, explainers, and tools worth keeping.

Myth Buster· 4

Myth Buster35:00

Healthy Snacking Wasn't the Problem—Late-Night Timing Was

In Berry's observational cohort of about 1,000 people, eating frequency within the studied range was not associated with worse outcomes when snacks were healthy. By contrast, she says snacking after 9 p.m. was associated with less favorable measures including abdominal fat, inflammation, and blood lipids, even for healthy snacks; this was an association, not proof that the timing caused those outcomes.

  • The cohort compared eating habits with multiple health measures
  • Berry reports no adverse signal from three versus roughly six healthy eating events
  • About 30% of participants reportedly snacked after 9 p.m.
  • Late snacking was associated with less favorable health markers
  • The episode does not establish that 9 p.m. is a universal causal cutoff

snacking per se wasn't a problem as long as they were healthy foods

Professor Sarah Berry · 36:30

that was associated with unfavorable Health outcomes

Professor Sarah Berry · 38:00
#snacking#meal timing#chrononutrition#association
Myth Buster1:02:00

Berry's Evidence-Based Rebuttal to Seed-Oil Toxicity Claims

Berry rejects viral claims that modern seed oils inherently cause inflammation, cancer, Alzheimer's disease, or obesity. She argues that rising seed-oil intake is confounded by many simultaneous lifestyle and dietary changes, that proposed omega-6 inflammatory pathways have not translated into harm in human trials, and that randomized-trial meta-analyses generally favor seed oils over saturated-fat comparators. These are Berry's evidence interpretations in the episode, not individualized medical advice.

  • Concurrent historical trends do not isolate seed oils as a cause
  • Berry says biochemical and test-tube mechanisms must be checked against human outcomes
  • She argues that omega-6 fats have not shown the predicted inflammatory harm in controlled human trials
  • She cites a meta-analysis of roughly 42 randomized trials comparing seed oils with other fats
  • Her conclusion depends partly on the comparator, especially saturated animal fats

there is absolutely no evidence that is credible evidence when interpreted in the correct way to show seed oils are harmful

Professor Sarah Berry · 1:03:00

what else has changed in that 50 years

Professor Sarah Berry · 1:05:30
#seed oils#omega-6#inflammation#nutrition myths#evidence
Myth Buster1:18:30

Why Berry Says Cheese, Yogurt, and Butter Shouldn't Be Grouped Together

Berry argues that dairy is too diverse to receive one health label. She says randomized trials show that ordinary portions of cheese and unsweetened yogurt do not raise cholesterol as butter can, despite similar saturated-fat content, and attributes the contrast partly to fermentation and food structure. Her comments concern typical intakes and do not establish that unlimited cheese is harmless.

  • Dairy includes liquid, solid, fermented, and non-fermented foods
  • Fermentation changes the food matrix
  • Berry reports different cholesterol responses to cheese and butter in randomized trials
  • She explicitly limits the claim to ordinary portions rather than very high intake
  • Butter is the less favorable comparator in her account

Dairy is a diverse food group

Professor Sarah Berry · 1:19:00

the butter will increase your cholesterol but the cheese will not

Professor Sarah Berry · 1:21:00
#dairy#cheese#yogurt#butter#cholesterol
Myth Buster1:21:00

Why High-Calorie Nuts Don't Automatically Cause Weight Gain

Berry says the totality of observational and clinical-trial evidence does not show weight gain when nuts are added to diets. She offers several possible explanations—including incomplete calorie absorption, satiety, microbiome effects, and a blunted blood-sugar response—while acknowledging that healthier overall habits can confound observational findings.

  • Nut consumers often have lower BMI in observational data, but may also have healthier diets
  • Berry says clinical trials do not show expected weight gain when nuts are included
  • She estimates that 20% to 30% of labelled nut calories may not be absorbed
  • Satiety and other metabolic effects may offset the nuts' high energy density
  • A package calorie value does not necessarily equal energy absorbed

the evidence does not support that

Professor Sarah Berry · 1:21:00

you only absorb 130 calories

Professor Sarah Berry · 1:22:00
#nuts#calories#weight#satiety

Hot Take· 1

Hot Take1:59:30

Berry's Case Against Dismissing Every Industry-Funded Study

Berry argues that industry funding should be disclosed and scrutinized but should not automatically invalidate nutrition research. Based on her university experience, she says funders have limited involvement in design, analysis, and publication, while acknowledging a separate concern: industry may influence which research questions receive funding. This is her account of the system, not proof that every funded study is independent or unbiased.

  • Government funding for nutrition trials is described as scarce and highly competitive
  • Berry says universities protect researcher control over analysis and publication
  • Funding disclosure remains necessary
  • Agenda-setting is a distinct concern from direct manipulation of results
  • Each study still requires scrutiny of contracts, methods, data access, and publication rights

we need to be able to get funding to be able to run studies

Professor Sarah Berry · 2:02:00

there is discussion about are they setting the agenda of that research

Professor Sarah Berry · 2:02:30
#research funding#food industry#conflicts of interest#nutrition science

Explainer· 7

Explainer26:00

Why Whole-Food Fiber and Added Fiber Are Not Quite the Same

Sarah Berry says UK adults are advised to consume at least 30 grams of fiber but average about 20 grams. She distinguishes soluble and insoluble fiber, argues that whole-food sources provide structural benefits, and still considers added fiber preferable to none.

  • Berry says most people in the UK do not reach the recommended fiber intake
  • She describes soluble fiber as relevant to cholesterol absorption and food metabolism
  • She describes insoluble plant fiber as supporting stool bulk and the gut microbiome
  • Her hierarchy is whole-food fiber first, while added fiber can still contribute

we should be getting at least 30 grams of fiber in the UK

Professor Sarah Berry · 26:30

having any kind of fiber is going to improve our health

Professor Sarah Berry · 28:00
#fiber#whole foods#gut health#microbiome
Explainer29:30

What Berry's Six-Week Almond Snack Study Actually Measured

Berry describes a randomized snack-swap study comparing almonds with a specially designed snack reflecting the UK's typical high-sugar, high-saturated-fat, low-fiber snack profile. She says the measured improvement in blood-vessel function was interpreted as equivalent to an estimated 30% reduction in cardiovascular-disease risk; the study did not observe a 30% fall in actual disease events. Berry also discloses Almond Board of California funding and says the funder did not control the study design, data, or pre-publication paper.

  • Participants obtained 20% of their energy from one of the assigned snack patterns for six weeks
  • The measured endpoint was flow-mediated dilation, a marker of vascular function
  • The cardiovascular-risk figure was an interpretation of the marker, not a count of prevented heart attacks
  • Berry says similar snack-substitution findings have appeared with other nuts
  • She explicitly discloses the study's industry funding

can we improve People's Health

Professor Sarah Berry · 29:30

I have actually had funding from the alma board of California

Professor Sarah Berry · 32:00
#snacking#almonds#vascular health#clinical trial#funding disclosure
Explainer41:30

How Poor Sleep Can Stack Hunger, Food Choice, and Glucose Response

Berry connects evidence suggesting that short or poor sleep can increase hunger, shift food choices, and worsen the same person's post-breakfast glucose response. She cites the Slumber study, in which short sleepers given sleep-hygiene advice who extended their sleep reduced free-sugar intake without dietary instructions, while carefully noting that some sleep findings are outside her own research.

  • Sleep duration, efficiency, and timing may affect hunger and fullness signals
  • Berry says the Slumber study gave sleep advice rather than dietary advice
  • Participants who extended sleep reportedly reduced free-sugar intake by about 10 grams
  • ZOE research found a higher post-meal glucose response after a poor night's sleep within the same person
  • The combined pattern can create what Berry calls a perfect storm rather than one isolated effect

if you've had a poor night's sleep You Reach For Less healthy food

Professor Sarah Berry · 42:30

those who were able to extend their sleep actually made healthier choices

Professor Sarah Berry · 43:00
#sleep#hunger#food choice#glucose
Explainer1:08:30

The Trans-Fat Detail Behind a Famous Anti–Seed Oil Study

Berry explains why she believes the 1970s Sydney study is often used misleadingly in modern seed-oil debates. The intervention relied on partially hydrogenated products that contained trans fats, so she argues that its worse outcomes cannot be cleanly applied to the non-hydrogenated seed oils commonly consumed today.

  • The trial involved men who had already experienced a cardiac event
  • The intervention increased omega-6 intake through products available at that time
  • Berry says partial hydrogenation generated harmful trans fats
  • Modern relevance depends on whether the historical product matches today's oil
  • The segment illustrates how cherry-picking can omit a decisive formulation detail

the majority of seed oils underwent an industrial process called partial hydrogenation

Professor Sarah Berry · 1:09:30

it's not how seed oil is consumed now

Professor Sarah Berry · 1:10:00
#seed oils#trans fats#study interpretation#history
Explainer1:22:30

Dietary Cholesterol Is Not the Same as Circulating LDL

Berry separates cholesterol eaten in food from cholesterol produced and transported by the body. She says typical dietary cholesterol intake—such as one or two eggs a day for most people—has little effect on circulating LDL, whereas saturated fat can increase liver production and reduce clearance of cholesterol. Her egg example is explicitly bounded and should not be read as universal advice.

  • LDL and HDL are transport particles carrying cholesterol to different destinations
  • Berry describes higher circulating LDL as an important cardiovascular-risk factor
  • She distinguishes food cholesterol from liver production of cholesterol
  • She says typical egg intake has minimal LDL impact for most people
  • Saturated fat and highly refined carbohydrate can affect liver cholesterol production

there are two ways that we can look at cholesterol

Professor Sarah Berry · 1:23:00

dietary cholesterol does not impact our circula cholesterol

Professor Sarah Berry · 1:25:30
#cholesterol#ldl#hdl#eggs#saturated fat
Explainer1:38:00

The Menopause Symptom Burden Hidden Behind Hot Flushes

Berry describes perimenopause as a fluctuating hormonal transition that can affect sleep, mood, cognition, body composition, and metabolic measures, not only temperature regulation. In ZOE survey data, she reports that brain fog and other brain-related symptoms were much more common than hot flushes, while emphasizing the broad burden women experience rather than reducing menopause to one symptom.

  • Berry defines menopause as one year after the last menstrual cycle
  • She says the transition commonly begins years earlier and can last from two to ten years
  • In ZOE data, 99% of surveyed perimenopausal women reported at least one symptom
  • She reports brain-related symptoms in roughly 85% and hot flushes in about 40%
  • Survey prevalence describes the studied respondents and does not diagnose an individual

99% of per menopause or women experience at least one menopausal symptom

Professor Sarah Berry · 1:42:00

hot flushers are the one of the least common symptoms

Professor Sarah Berry · 1:43:30
#menopause#perimenopause#brain fog#women's health
Explainer1:51:00

Diet and Menopause Symptoms: Promising Results, Important Limits

Berry says a healthier, Mediterranean-style pattern emphasizing plant diversity and fiber may reduce menopause symptoms, but she clearly distinguishes stronger and weaker evidence. Her ZOE subgroup reported a 35% symptom reduction over 12 to 18 weeks without a control group, while other randomized studies reportedly found a similar reduction near 30%; neither result makes diet a universal replacement for HRT or clinical care.

  • Berry says HRT can help many symptoms but is not suitable or preferred for everyone
  • The ZOE analysis followed dietary change without a randomized control arm
  • She explicitly says the 35% estimate needs controlled replication
  • She cites randomized Mediterranean-diet studies with a similar approximate effect
  • Evidence for most marketed menopause supplements is described as weak

there isn't a one siiz fix it's all there isn't a silver bullet

Professor Sarah Berry · 1:52:00

there wasn't a control arm

Professor Sarah Berry · 1:53:00
#menopause#mediterranean diet#hrt#study limitations#supplements

Story· 1

Story2:05:00

Why Caring for Her Mother Outranked Becoming a Professor

Berry says four years caring for her mother through a degenerative neurological condition changed her perspective on ambition and achievement. Although proud of becoming a professor and being the first in her family to attend university, she identifies caregiving as her greatest achievement and now places more weight on relationships, joy, and being a kind person.

  • Berry took a career break and shared full-time care with her family
  • Watching her mother lose basic abilities changed what Berry values
  • She remains proud of her academic achievement without treating it as the highest form of success
  • Her closing principle is to enjoy the present and avoid overcomplicating life

all that matters is that you have good relationships that you're finding joy in life

Professor Sarah Berry · 2:05:00

what I'm most proud of is the four years that I cared for my mom

Professor Sarah Berry · 2:08:00
#caregiving#perspective#success#relationships#grief