Hello my friends and fellow haemoglobin smugglers!  This week I'm going to cover: an easy way to monitor your hydration levels (lessons learned from hospital shifts!), how to eat high fiber but low calorie when dieting and effective non-drug ways to low cholesterol! 

The Easiest Way to Know if You’re Drinking Enough Water

Ok so we’ve all heard this before: “Eight glasses of water a day.” 

Or, depending on where you live, six cups, eight cups, a gallon if you’re in the gym-bro corner of TikTok.

So, who’s right?

Well…there is no single “magic number.”

A 2016 study by the University of Stirling tested a range of drinks; including coffee, tea, even beer and found they hydrated just as well as water in normal amounts. (Yes, that morning flat white still counts.)

So why the confusion around how much to drink? Hydration is very personal. Your needs depend on your body size, diet, activity level, and environment. Someone running a 10k in the Texas heat isn’t the same as someone typing in an air-conditioned London office.

Here’s the real science-backed way to know if you’re drinking enough:

1. Count your bathroom trips

Based on evidence and physiology this is a simple, practical marker: pee frequency.

• If you’re hitting the throne 4–6 times a day, you’re probably in the hydration sweet spot.
  

• Fewer than 4: You might need to top up.
  

• More than 6: You could be overdoing it.
  

This rule accounts for individual differences in sweat, food intake, and climate; things a “6-8-cups-a-day” rule ignores.

2. Check your urine colour

Another quick biofeedback trick: urine colour.

• Pale yellow = well hydrated.
  

• Dark amber = probably need more fluids.
  

• Crystal clear all day long: You might be flushing out too much.
  
  

Think of it as your body’s built-in dipstick test.

A few caveats

Of course, this isn’t a one-size-fits-all diagnostic. Age, kidney function, medications (like diuretics aka water tablets), and even the type of drink you consume can change the picture. That’s why it’s better to use a combo of markers; thirst, toilet frequency, and urine colour… rather than relying on just one.

Actionables you can use today

1. Don’t fear coffee or tea → They hydrate too (as long as you’re not pounding ten espressos).
   

2. Eat your water → Cucumbers, watermelon, oranges, soups; all count toward hydration.
   

3. Front-load in the day → A few glasses in the morning help kickstart metabolism and keep you sharp.
   

4. Listen to your body → Dry mouth, headaches, fatigue = classic dehydration cues.
   
   

Forget chasing arbitrary numbers; your body leaves clues so aim to pee 4–6 times daily, keep urine pale yellow, and trust your thirst - simple, effective, science-backed!

Quick interlude: If you think The Weekly Dose is cool 😎, share this newsletter on socials, mention it in your newsletter, and/or hit forward to your health-curious friends, family, and that one fiendish coworker who loves learning about health stuff.

Reminder: This newsletter is free, always will be and I send it out every Sunday to give you in-depth insights into the health topics!

Low Calorie, High Fiber Foods…

Here’s a hard truth I learned the messy way… hitting 30g of fiber a day while on a calorie deficit is no small feat.

Fiber is one of the most underrated tools in weight management. It slows digestion, blunts blood sugar spikes, supports hunger hormones like GLP-1 and PYY, and literally feeds the microbes that help regulate your metabolism. In fact, meta-analyses show higher fiber intake is linked to lower body weight and reduced risk of obesity.

But paradoxically the act of dieting itself can backfire on your gut. Calorie restriction sometimes slows gut motility (a form of “mini-gastroparesis”), which means bloating, constipation, or sluggish digestion. That’s exactly when you need fiber the most… and ironically, that’s when it’s hardest to hit your daily target.

Why you ask? Because a lot of high-fiber foods also pack calories. 

Like almonds… fantastic source of fiber but a small handful can cost you 200+ calories or avocados… brilliant for gut health but half of one is ~120 calories. Great foods, but not always “budget-friendly” when you’re counting calories.

So how do you hit your fiber goals without blowing your calorie bank?

Low-calorie, high-fiber heroes (realistic servings)

These are the foods that give you the most “fiber bang for your calorie buck.” (everything is listed per 100g btw)

Fruits

Raspberries → 6.5g fiber, ~52 kcal

Blackberries → 5.3g fiber, ~43 kcal

Blueberries → 2.4g fiber, ~57 kcal

Strawberries → 2.0g fiber, ~32 kcal

Pear (with skin) → 3.1g fiber, ~57 kcal

Apple (with skin) → 2.4g fiber, ~52 kcal

Orange → 2.4g fiber, ~47 kcal

Vegetables

Broccoli (raw) → 2.6g fiber, ~34 kcal

Brussels sprouts → 3.8g fiber, ~43 kcal

Cauliflower → 2.0g fiber, ~25 kcal

Carrots → 2.8g fiber, ~41 kcal

Zucchini → 1.1g fiber, ~17 kcal

Green beans → 3.4g fiber, ~31 kcal

Spinach → 2.2g fiber, ~23 kcal

Legumes (more calorie dense, but fiber bombs)

Chickpeas (cooked) → 7.6g fiber, ~164 kcal

Lentils (cooked) → 7.9g fiber, ~116 kcal

Black beans (cooked) → 8.7g fiber, ~132 kcal

Edamame (cooked) → 5.0g fiber, ~122 kcal

Seeds & extras

Chia seeds → 34g fiber (!!), ~486 kcal (10g serving = 5g fiber, ~50 kcal)

Flaxseeds → 27g fiber, ~534 kcal (10g serving = 2.7g fiber, ~53 kcal)

Sunflower seeds → 8.6g fiber, ~580 kcal (small handful = 3–4g fiber)

Air-popped popcorn → 14g fiber, ~387 kcal per 100g (but 3 cups = ~90 kcal, ~3.5g fiber)

Quick practical swaps (equal calories, more fiber):

Grapes (100g: 0.9g fiber, 69 kcal) → Raspberries (100g: 6.5g fiber, 52 kcal)

Cucumber (100g: 0.5g fiber, 15 kcal) → Green beans (100g: 3.4g fiber, 31 kcal)

White rice (100g cooked: 0.4g fiber, 130 kcal) → Lentils (100g cooked: 7.9g fiber, 116 kcal)

The volume eating trap

A lot of people lean on “volume eating” in calorie deficits: giant salads, massive bowls of low-cal veg. It works… up to a point. But without a focus on fiber specifically, you can end up with food that looks impressive in size but does little for satiety or microbiome health. Lettuce is mostly water. Berries and beans are fiber gold.

The secret isn’t just filling your plate… it’s making sure what’s on it fuels your gut microbes and keeps hunger hormones in check.

Actionables this week

1. Audit your fiber → Track a normal day and see where you land (most people don’t even hit 15g).
   

2. Swap smarter → Grapes (1g fiber/cup) → Raspberries (8g fiber/cup). Easy upgrade.
   

3. Spread it out → Don’t drop 20g of fiber in one sitting. Aim for 5–10g per meal.
   

4. Hydrate → Fiber needs water to move. Pair every 10g of fiber with ~250ml (10-12oz) fluid.

   
   

Fiber isn’t just about pooping better. In a calorie deficit, it’s your metabolic safety net…helping you stay fuller, regulate hormones, and keep your gut moving.

P.S. After years of trial and error with fiber supplements that bloated me, clumped like cement, or did nothing for my microbiome, I created LOAM ; a precision prebiotic fiber blend that’s diverse, clinically backed, and gentle on the gut. Think of it as a multivitamin for your microbiome. If you’d like priority access when it launches (yes, available in the US), join the waitlist here:

P.P.S If you scroll to the end of the newsletter you’ll see some more high fiber, low calorie meal and snack ideas! With that and the fiber cheat sheet I sent you when you signed up you should be in fiber heaven!

P.P.P.S if you sign up at www.loamscience.com you’ll also get weekly tips to improve your gut and microbiome health too! :)

The Best Way to Lower Cholesterol Without Statins

Before I continue, I’m not advocating for stopping your statins or any medical intervention if it is needed… this is simple lifestyle related information to improve your health! 

First… here’s a medical riddle for you:

How can something your body needs to survive also be the same thing that slowly clogs your arteries and triggers heart attacks?

Answer: cholesterol (duh...it’s in the title lol)

We often treat it like the villain of every heart health story. But cholesterol itself isn’t the bad guy… it’s the way it travels.

Think of cholesterol as passengers, and your bloodstream as the motorway. These passengers hitch rides in vehicles called lipoproteins. The problem is that some of those vehicles; LDL, the so-called “bad cholesterol”...are reckless drivers. They smash into the lining of your arteries, get stuck, and over time cause a dangerous build-up of plaque.

Almost half of UK adults and 1 in 10 Americans have cholesterol levels that put them at risk, often without realising it.

So yes, statins exist, and they save lives. But unless your levels are dangerously high, you can make serious changes without a prescription.

Movement: nature’s statin

Regular aerobic activity… walking, cycling, swimming… can lower LDL and raise HDL (the “good” cholesterol) by about 5%. Not huge on paper, but small changes compound over time. Pair that with quitting smoking (yes, vaping too), and you’ve already changed the odds.

Food: the real game-changer

Here’s where the biggest difference comes from.

Soluble fiber (found in oats, beans, lentils, apples, nuts, seeds) binds to cholesterol in your gut and helps you excrete it instead of absorbing it. A bowl of oats a day really can nudge your numbers in the right direction.

Plant sterols and stanols… natural compounds in some fortified spreads, yoghurts, or supplements…trick your gut into absorbing them instead of cholesterol. The result is up to a 10% reduction in LDL.

Cutting back on saturated fats and ultra-processed foods (like processed meats, pastries, deep-fried foods) reduces the strain on your liver’s ability to regulate cholesterol. Less traffic on the motorway, fewer pile-ups.

What about eggs?

Old-school advice said avoid egg yolks because they’re high in cholesterol. The science now says dietary cholesterol doesn’t equal blood cholesterol for most people. Your liver makes around 80% of the cholesterol in your blood. The real culprits are saturated fat and sugar, which mess with your liver’s ability to clear LDL.

So no, your Sunday poached eggs aren’t killing you.

Takeaways you can use this week

Breakfast swap: Oats with berries + chia instead of pastries.

Lunch swap: Lentil or chickpea salad instead of processed meat sandwich.

Snack swap: A handful of nuts instead of crisps.

Consistency: Aim for at least 25–30g of fiber daily (spoiler: 95% of people miss this target).

To reiterate, statins are life-saving when you need them. But for many, the best first-line therapy isn’t a pill… it’s your plate. Small, consistent changes in what you eat and how you move can dramatically reshape your cholesterol profile and reduce long-term heart risk.

Your life does not demand perfection but balance.

👋 Who are you again? I’m Karan Rajan - a doctor and curious explorer of all things health and wellness. I host the Dr Karan Explores Podcast and have written two books "This Book May Save Your Life" and "This Is Vital Information" and have just founded a microbiome company, LOAM Science 

Every Sunday, I share 3 interesting things about health, life and science to make your life easier, healthier and happier. (Disclaimer: I’m more your friend with health benefits. None of this is medical advice.) 

And oh, you if also feel strongly about some health things or just want to say hi? Hit reply... I’d love to hear it and hear from you!

Thanks for reading to the end, btw don’t forget to check out these high fiber, low-calorie meal and snack ideas:

No-prep snack combos

100g raspberries + 2 tbsp chia seeds → ~11g fiber, 150 kcal

3 cups air-popped popcorn + 1 small apple → ~6g fiber, 160 kcal

200g steamed broccoli + squeeze of lemon → ~5g fiber, 70 kcal

The key is choosing foods with high “fiber per calorie” density.

That’s why berries, brassica veggies, and popcorn are unbeatable for dieting: you can eat a LOT, stay full, and keep calories in check.

Easy meal ideas (minimal to no prep)

 1. Crunchy snack box

1 medium carrot (60g) → 1.7g fiber

1 apple with skin (150g) → 3.6g fiber

20 almonds (28g) → 3.3g fiber

Total: ~8.6g fiber

2. 3-Minute yoghurt bowl

200g plain Greek yoghurt (unsweetened) → 0g fiber (but protein + calcium bonus)

100g raspberries → 6.5g fiber

1 tbsp chia seeds (10g) → 3.4g fiber

1 tbsp ground flaxseed (10g) → 2.7g fiber

Total: ~12.6g fiber

3. Gut-friendly smoothie

1 banana (120g) → 3.1g fiber

100g spinach → 2.2g fiber

½ avocado (75g) → 5g fiber

200ml unsweetened almond milk → 1g fiber

Total: ~11.3g fiber

4. High-fiber movie snack

3 cups air-popped popcorn (~24g) → 3.5g fiber

1 small pear with skin (100g) → 3.1g fiber

Total: ~6.6g fiber

5. Microwave veggie bowl

200g steamed broccoli (microwave bag) → 5.2g fiber

150g chickpeas (canned, drained) → 7.6g fiber

Squeeze of lemon + sprinkle of salt → 0g

Total: ~12.8g fiber

6. Quick fiber sandwich

2 slices wholegrain bread (~70g) → 6g fiber

50g hummus → 2g fiber

50g cucumber → 0.5g fiber

50g roasted red peppers → 1.5g fiber

Total: ~10g fiber

7. 5-Minute lentil salad

150g canned lentils (drained) → 6.7g fiber

100g cherry tomatoes → 1.2g fiber

50g arugula/rocket → 0.8g fiber

1 tbsp olive oil + lemon → 0g

Total: ~8.7g fiber