Issue #4 - Betaine-rich Foods & Biological Clocks

Welcome to Weekly.health’s fourth issue. Every week, we explore cutting-edge research, actionable advice, and science-backed nutrition insights to help you live longer and healthier.

Our aim is to help you live another 10 healthy years and cut your risk of age-related disease.

🗒️ In This Issue:

• 🔢 Weekly.health in numbers

• 🔬 Longevity Spotlight: Betaine, biological clocks, and curcumin

• 📈 Research Digest: What’s new in nutrition science

• 📰 Previous Issues of Weekly.health: A reminder

• ❤️ Support Weekly.health: Help us keep the research flowing

• 📘 Glossary of Terms: Definitions for technical terms in this issue

🔢 Weekly.health in numbers

In the 4 weeks since launching Weekly.health’s first issue we’ve sent over 1,000 emails to health and nutrition fans around the world.

Our first issue, which you can read here, was sent to just 6 subscribers. We now have more than 500, and 40 new subscribers join us every day.

Each issue is a result of many hours of sifting through the latest research and plotting out actionable takeaways to improve your health.

Each issue should also only take 10 minutes for you to read each week.

The benefit to your health, we think, is worth a lot more.

Thank you for joining us on our journey to make everyone a little healthier.

☕ If you’d like to, you can also be the first to support us here

🔬 Longevity Spotlight: Betaine, Biological Clocks, and Curcumin

Ageing (or aging for our American subscribers) is possible to slow down, a number of clinical reviews suggest. This week, a review of betaine-rich foods suggest the nutrient may improve several markers of ageing, while a review of biological clocks shows it’s possible to calculate our pace of ageing. If you’re up for a challenge, why not take before and after tests alongside improvements to your diet and fitness to see the impact of your changes?

• Consume more betaine-rich foods to slow ageing: Betaine, a nutrient found in quinoa, spinach, and whole grains, may help slow ageing. This recent review highlights its role in improving DNA methylation (which declines with age), reducing harmful homocysteine (linked to heart and brain diseases), supporting muscle and bone health, and lowering inflammation and oxidative stress. Current average intake is around 182 mg/day, but higher amounts may be needed to see benefits. (source)

  • Foods containing betaine per 100g;

    • Wheat bran - 1,339 mg

    • Wheat germ - 1,241 mg

    • Spinach - ~645 mg

    • Beets (raw) - ~115–130 mg

    • Pretzels - ~237 mg

    • Shrimp - ~218–246 mg

    • Whole‑wheat bread - ~201 mg

    • Quinoa - ~630 mg

• Biological clocks use simple health data to predict mortality: 
  A new review analysed 33 studies on "biological clocks”, tools that estimate how fast you're aging. Phenotypic clocks use simple health data like blood pressure and glucose, while epigenetic clocks look at DNA methylation. The takeaway? Phenotypic clocks are cheaper, easier, and better at predicting mortality. To track your healthspan, keep tabs on your blood markers, and take tests such as PhenoAge and GrimAge for insights into your pace of ageing. (source)

• Curcumin helps counteract age-related inflammation and more: This 2024 review analysed 15 clinical trials on curcumin (from turmeric) and found it may help counteract age-related inflammation, oxidative stress, and mitochondrial dysfunction. Daily doses between 50–300 mg/kg in animals and up to 2g/day in humans improved memory, reduced Alzheimer’s-related brain changes, and helped prevent muscle loss (sarcopenia). For healthy ageing, consider adding curcumin to your diet - but opt for bioavailable forms for better absorption. (source)

👉 Add wheat bran and wheat germ to your cereals and smoothies for a betaine-hit, and add turmeric to all sauces to get your daily curcumin dose.

📈 Research Digest: What’s New in Nutrition Science

Here’s the best of recent nutrition research:

⏩ A Full 24-hour Fast Every Other Day Produces Greater Weight Loss
A large analysis of 99 clinical trials and over 6,500 participant found that alternative day fasting (ADF), 24 hours of fasting every other day, leads to slight more weight loss than time-restricted eating, whole day fasting, or standard calorie-cutting diets. ADF resulted in about 3.4kg weight loss in stort-term trials, while other fasting methods produced about a 2kg weight loss. Long-term, all diet strategies were comparable. Our takeaway from this review is that ADF is best used at the start of a new weight-loss regimen for the most substantial results. (source)

😴 Sleep Less, Move Less, Eat Worse: How Poor Sleep Impacts Healthy Choices
Cutting sleep from 8-9 hours to just 5-6 hours a night for one week led to a significant drop in physical activity in one study. Losing sleep generally didn’t make people eat more, but some participants chose less healthy foods and drinks, prioritising taste over their health - some reported consuming more fat and sugar. Try to get around 8 hours of sleep each night and you may find other aspects of health, such as exercise and nutrition, feel a little easier. (source)

🍴 Add Meal Replacement Drinks to Intermittent Fasting for Faster Weight Loss
An 8-week Chinese study found that adding meal replacements to a 5:2 intermittent fasting routine (restricting calories for two days per week) led to more rapid fat loss than a standard calorie-restricted diet alone. Participants on the 5:2 schedule consumed a 205 kcal nutritional powder drink three times per fasting day, and followed a standard calorie-restricted diet five days per week. The 5:2 group lost 8.2% of body weight compared to 5.8% in the non-replacement group. Both groups improved health markers. Meal replacements reduce the risk of overeating due to pre-measured macronutrients and calories. (source)

📰 Previous Issues of Weekly.health

In this section we usually cover one health topic in detail, but considering the fast growth of Weekly.health in recent weeks, we wanted to remind you of our previous issues and the research you might have missed.

Here are summaries of the three latest Weekly.Health newsletters, but please click through to read the issues online for full details:

🥗 Issue #1 – “Live Longer Through Diet” (26 June 2025)

• Longevity spotlight: Simple daily habits—wholegrains, meditation, blueberries—support cellular health and reduce inflammation, blood pressure, and cognitive decline

• Research highlights:

  • A late breakfast (~10:30 am) helps stabilise blood sugar

  • High protein diets cut caloric intake and boost metabolism

  • Pre‑workout carbs and evenly spaced protein intake aid women’s performance

• Morning routine tip: Swap cow’s milk for plant-based milks and coffee for green tea to support heart health and cognition

• Nutrition lesson: Detailed overview of fats—types, benefits, and how to balance intake for longevity

• Food spotlight: Avocados—rich in monounsaturated fats and fibre—linked to improved heart health, skin elasticity and 50 % lower metabolic syndrome risk

🥦 Issue #2 – “Varied, Balanced Diets for Healthier Lives” (3 July 2025)

• Longevity spotlight: Culturally adapted diets full of plants and low in ultra‑processed foods help reduce LDL cholesterol and slow telomere shortening

• Research highlights:

  • Curcumin (1,500 mg/day) reduces inflammation and body fat in diabetics

  • Joining plant-based community programmes yields sustained weight loss

  • Nutrition literacy reduces stress more than exercise

• Dementia prevention: Combining exercise, cognitive training, healthy diets (Mediterranean/MIND), good sleep, and stress reduction may cut dementia risk by up to 45 %

• Balanced plate guide: Half veg/fruit, quarter wholegrains, quarter protein; include healthy fats; limit processed foods and sugars; adapt to your cultural preferences

• Food spotlight: Legumes—beans, lentils, chickpeas—linked to 6–16 % lower mortality, better metabolic health and weight loss

🚴 Issue #3 – “Exercise, Fasting, and the Mediterranean Diet” (10 July 2025)

• Longevity spotlight:

  • Collagen supplements show no true benefit when bias is removed

  • Combining aerobic, resistance and mind‑body exercise boosts physical and cognitive health in older adults

  • Blue Zones habits—natural movement, social connection, purposeful life—promote longevity

• Research highlights:

  • Four-week fitness + high-fibre + fermented foods regimen improves gut microbiome

  • Intermittent fasting (twice-weekly dawn-to-dusk) + healthy meals reduces visceral fat and cardiometabolic markers

  • Exercise alongside fasting doubles benefits—better fat loss, waist reduction, insulin control

• Air pollution & ageing: Indoor HEPA filters, masks, organic produce, and simple washing methods help protect against accelerated cellular ageing

• Mediterranean diet in 5 mins: Focus on colourful plant foods, whole grains, olive oil, lean proteins, nuts, moderate dairy, herbs—and minimise red/processed meats, refined carbs, ultra‑processed foods and salt

  • Benefits include 31 % reduced cardiovascular risk, 23 % lower T2 diabetes and overall mortality

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🍽️ 5 Activities to Improve Your Diet in 5 Minutes

1. 7-Day Food Snapshot

Write down everything you eat and drink for 7 days (including snacks, drinks, and condiments). Use your phone notes, a simple notebook, or a tracking app like Cronometer or MyFitnessPal.

Next to every item, mark it as ‘More’, or ‘Less’, depending on whether you think you should be consuming more or less of it.

• For fruits, vegetables, nuts, legumes and other plant foods, always mark these down as ‘More’.

• For meats, eggs, and dairy, mark them down as ‘Less’.

• If you consume less than one portion of fatty fish (salmon, sardines, etc.) per week, mark fatty fish down as ‘More’, unless of course your diet doesn’t permit animal products.

• For any products in a packet or box that contain more than 5 ingredients, or any number of ingredients where sugar or some variation of syrup is listed, mark these down as ‘Less’.

• For any product that contains more than 10g/100g of fibre, alongside less than 5g/100g of sugar, mark these down as ‘Much more’ and consume them much more often.

Most people underestimate how much processed food, added sugar, or saturated fat they actually consume, and overestimate the amount of fibre. Seeing it in black and white highlights patterns you might miss day to day.

For the next week, week, follow your list and consume these foods More or Less often than you did during the first week.

2. The Colour Count Challenge

Each day for a week, count how many different colours of plant foods you eat (fruits, vegetables, herbs, spices, whole grains, beans, nuts). Aim for at least 5 different colours per day as a minimum.

Dietary diversity improves gut health, provides a wider range of nutrients, and is linked to longevity.

For the next week, try to maximise the colours you consume. See just how many you can fit onto a plate, and think about how that affects the variety of nutrients and plants you’re consuming.

3. Ultra-Processed Food Audit

For one week, circle or list any packaged foods you eat. Look at the labels. If the ingredient list has 5+ unfamiliar or artificial ingredients, or you wouldn’t cook it that way at home, mark it as ultra-processed.

High ultra-processed food intake is linked to increased risk of obesity, heart disease, and early death, even when calorie intake is controlled.

For the next week, reduce your consumption of ultra-processed foods by at least half, and by the end of the week, think about any changes to your energy levels, mood, motivation, and your general wellbeing.

4. Protein Source Review

List the protein sources you’ve eaten in the last 7 days. Mark whether they are:

• Whole food & plant-based (e.g., beans, lentils, tofu, nuts)

• Whole food & animal-based (e.g., eggs, fish, chicken breast)

• Processed meats (e.g., bacon, sausages, deli meat)

The source of your protein may matter as much as the amount. Plant-based and minimally processed proteins are consistently linked with better long-term health outcomes.

For the next week, aim for 1 source of processed meats, or none. Aim for 3 sources of animal-based proteins, or fewer, with at least 1/3rd of these being fish. For any remaining foods, ensure they are plant-based proteins.

5. Added Sugar Scan

Check the labels on everything you consume for added sugar. Write down how many teaspoons you’re getting in a day. (4g sugar = 1 teaspoon)

The World Health Organization recommends no more than 25g (6 teaspoons) of added sugar per day for health benefits. Most people consume 2–3x this amount without realising it.

Once you understand your intake, aim to reduce it by one teaspoon a day, each week until your consumption is within or below the recommendation from the WHO.

📥 Support Weekly.health
Enjoying this issue? If you’ve found our deep dives into health and nutrition research valuable, you can support Weekly.health with a small donation.

Each issue takes a few days to create for our team - from reviewing dozens of new studies to distilling the most relevant findings into actionable insights. Your support helps us continue delivering evidence-based guidance to help you live a longer, healthier life.

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🙏 Thanks for Reading!

That’s the end of this issue of Weekly.health. We hope you learned something useful to help you on your nutritional journey.

This newsletter is written by a small, independent team, led by James — who’s been following nutrition science for nearly 20 years and is now working towards a formal, industry-recognised qualification.

We’re based in England, so if you’re over the pond, you might notice a few strange spellings.

Our goal is to make cutting-edge, evidence-based nutrition advice simple, useful, and genuinely applicable to everyday life.

We’ll keep improving with every issue. If you’ve got any feedback or suggestions, we’d love to hear them (just reply to this email).

See you next week!

📖 Glossary of Terms in This Issue (Alphabetical Order)

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