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How iron, folate, and vitamin B12 sustain red blood cell formation
Iron, folate, and vitamin B12 are essential nutrients that work together to make and mature red blood cells. Their metabolism is tightly controlled because even small deficiencies can impair oxygen delivery and DNA synthesis, leading to anemia.
1️⃣ Iron intake and absorption
Most adults need 10–20 mg of dietary iron per day, but only 3–15% is absorbed in the small intestine. Iron from meat (heme iron) is absorbed more efficiently than iron from plants (non-heme iron). Stomach acid helps convert ferric iron (Fe³⁺) to its absorbable ferrous form (Fe²⁺).
🟢 Example: Vitamin C enhances absorption by reducing Fe³⁺ to Fe²⁺, while phytates in grains or excess calcium reduce uptake.
2️⃣ Iron transport and storage
Once absorbed, iron binds to transferrin, the blood’s transport protein, and is delivered to tissues like the bone marrow for red blood cell production. Surplus iron is stored in the liver as ferritin and hemosiderin. The hormone hepcidin from the liver regulates iron export—high levels block release, preventing overload.
🟢 Example: In chronic inflammation, hepcidin rises, trapping iron in macrophages and leading to “anemia of chronic disease.”
3️⃣ Iron recycling
When red blood cells break down, macrophages in the spleen and liver recover the iron from hemoglobin and return it to circulation. This recycling process supplies most of the daily iron needed for new red blood cell formation.
🟢 Example: The body recycles about 25 mg of iron each day, far exceeding the amount absorbed from food.
4️⃣ Folate and vitamin B12 absorption
Folate is absorbed in the small intestine, while vitamin B12 requires intrinsic factor from the stomach for uptake in the ileum. Both nutrients are stored in the liver and used for DNA synthesis in developing red blood cells.
🟢 Example: Vitamin B12 intake averages just 1 microgram daily, but liver stores (≈2–5 mg) can last for years, while folate stores deplete within months if intake falls.
5️⃣ Shared role in erythropoiesis and DNA synthesis
Inside bone marrow, folate and B12 cooperate to generate tetrahydrofolate, a cofactor for DNA and red cell production. Without them, cells enlarge without dividing properly, producing megaloblastic anemia.
🟢 Example: B12 deficiency traps folate in its inactive (i.e., unable to donate it's methyl group to methionine synthase) form (“methyl-folate trap”), halting DNA replication and leading to fatigue, pale skin, and neurological symptoms.
Efficient red blood cell production depends on the seamless interaction between iron supply, folate metabolism, and vitamin B12 activation. When any link in this triad breaks, oxygen transport falters and anemia develops—a sign that cellular energy and repair are being starved at the molecular level.
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Metaflammation’s Role in Systemic Dysfunction in Obesity: Gut Barrier Impairment → Dysbiosis → Endotoxemia → Chronic Low-Grade Inflammation → Insulin Resistance, Neuroinflammation, Reproductive Dysfunction & Cardiovascular Risk.
A single pathway links microbial imbalance to multi-organ pathology.
Citation:
Tian, Y., Xu, Z., Li, S., et al. Metaflammation: Chronic low-grade inflammation in metabolic disorders. Pharmacological Research, 2023; 187:106552.
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Glad to share our most recent @SpringerNature view on #interferon and #cancer #immunity! Kudos to Ainhoa and @EmmaGuilbaud for doing the heavy lifting here, and to Santos Mañes for critical input! Available at link.springer.com/10.1186/s1… @FoxChaseCancer @CNB_CSIC
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NEW content online! Epigenetic regulation of T cell exhaustion in cancer bit.ly/4oHxa6h
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Chemistry writes the story of life.
Every cell, every second, it tells it again - powered by molecular design.
At the core of this process lies the citric acid cycle, the central hub of metabolism.
Here, acetyl-CoA derived from carbohydrates, fats, or proteins enters a precise series of reactions that convert fuel into energy.
Each step transfers electrons, drives ATP synthesis, and sustains the continuous renewal of life at the cellular level.
What may seem invisible is, in fact, the most constant motion in existence; the quiet rhythm of biochemistry that powers everything we do.
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3 types of hunger explained "simply"
Hunger isn’t just about an empty stomach. Your brain receives signals from body composition, hormones, emotions, and even gut microbes. Here’s how the three major types work:
1️⃣ Homeostatic Hunger (Energy Balance Hunger)
This is your body’s “fuel gauge.” It rises and falls based on energy needs and metabolic signals.
What drives it: Ghrelin from the stomach stimulates hunger; leptin from fat cells and incretin hormones (GLP-1, PYY, CCK) reduce it.
What it does: Ensures your intake matches your energy needs for exercise, growth, and tissue repair.
🟢 Example: After a long run, homeostatic hunger pushes you to replace calories and glycogen.
2️⃣ Hedonic Hunger (Reward-Driven Hunger)
This is your “food pleasure” system. It’s triggered by sight, smell, habits, and emotions, not by actual energy needs.
What drives it: Brain reward circuits activated by highly palatable foods (sugar, fat, salt).
What it does: Encourages eating even when you’re not truly hungry. Weak satiety signals make it harder to stop.
🟢 Example: Craving dessert after dinner even though you’re full.
3️⃣ Microbiota-Driven Hunger (Gut Microbe Hunger)
Your gut bacteria also shape hunger signals by producing metabolites that influence hormones and the brain.
What drives it: Microbes generate compounds that mimic hunger or satiety signals, affect insulin, and modulate ghrelin, GLP-1, and PYY.
What it does: Links gut health to appetite regulation and metabolic control.
🟢 Example: Certain bacterial imbalances may increase cravings or weaken satiety, nudging overeating.
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Review of IL-1 family cytokines in inflammation and immunity - including, IL-1, IL-18, IL-33, IL-36, IL-37, IL-38, IL-1Ra, etc. Full read -- Good Reference!! buff.ly/jmT18rl
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A simple guide to how mitochondria work. 4️⃣ primar jobs
Mitochondria are more than the “powerhouse of the cell.” They’re multitasking organelles that control energy, stress, genetics, and even cell survival. Here are the 4 primary jobs they do:
1️⃣ ATP Generation (Energy Production)
Mitochondria convert glucose, fats, and amino acids into acetyl-CoA, which enters the TCA cycle and electron transport chain (ETC).
The result: ATP, the energy currency for everything from nerve signals to muscle contractions.
🟢 Example: Every time you move or think, mitochondria are fueling the process.
2️⃣ ROS Balance - i.e., redox control
As mitochondria make ATP, they also generate reactive oxygen species (ROS) damaging byproducts.
Antioxidant enzymes (like catalase, SOD, glutathione peroxidase) keep ROS under control.
Too much ROS = oxidative stress → cell injury or death.
🟢 Example: Exercise trains mitochondria to better balance ROS, which is one reason it’s so protective.
3️⃣ mtDNA Maintenance (genetic stability)
Mitochondria have their own DNA (mtDNA), which encodes key ETC proteins.
Damage or mutations in mtDNA reduce energy output and contribute to diseases.
mtDNA mutations accumulate with age, linking mitochondria to neurodegeneration and aging.
🟢 Example: Mitochondrial DNA damage is a hallmark in Alzheimer’s and Parkinson’s disease.
4️⃣ Membrane Dynamics (fission & fusion)
Mitochondria constantly split (fission) and merge (fusion) to adapt to stress and demand.
This dynamic reshaping controls quality, removing damaged mitochondria (mitophagy) and keeping networks healthy.
🟢 Example: Impaired fission/fusion is seen in metabolic disorders and neurodegenerative disease.
Mitochondria don’t just make energy. They balance oxidative stress, protect genetic integrity, and constantly remodel themselves to keep cells alive. Supporting mitochondrial health means supporting the foundation of cellular life.
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Lipids simplified!
🧱 Cholesterol – is the material needed for building cell walls, making hormones etc
🛻 Lipoproteins - are basically Trucks transporting Cholesterol along with other things through blood. Depending on size they are of many types.
⛽ Triglycerides – are portable Fuel containers that trucks are carrying along.
🚛 HDL – They are the Recycling Trucks the patrol the roads collecting leftover cholesterol bricks from tissues & arteries, & bringing it back to the liver’s recycling center. HDL- C in your reports is the total leftover bricks in circulation currently.
🚚 LDL – They are the Delivery Trucks that deliver cholesterol bricks from the liver warehouse to construction sites (cells) around the body. LDL- C in your reports is the total unused bricks in circulation currently.
🚨 Lp(a) - Some of these LDL delivery trucks have an extra problem. They are wheel that are extra sticky.
🚛📦 VLDL – They are the Fat Cargo Trucks that mainly transports big boxes of triglycerides (fat) from the liver to storage sites.
🪪♦️ApoB (Apolipoprotein B) - All the main delivery trucks (LDL, Lpa, VLDL..) have a common license plate called ApoB. Counting them gives an idea of the no of trucks on road currently. More means too many cholesterol bricks & extra fuel (Tg) are being transported
🪪🔹ApoA1 (Apolipoprotein A1) - The recycling trucks have a different license plate called ApoA1. If more of these license plates are in action means more cleanup is done.
—————
What to Target?
▶️ Total Cholesterol:
This number is important, but the break up is more important (usually high means more LDL, VLDL… hence a problem)
- Total Cholesterol of around 200 with the right breakup is ideal 🟢
- Too Low & Too High is not ideal 🔴
▶️ HDL-C:
More cleaned up bricks is always better
- For men > 40 mg/dL 🟢
- For women > 50 mg/dL 🟢
▶️ Triglyceride:
Lot of portable Fuel being transported means excess energy/calories in the system.
- Ideal: < 100 mg/dL 🟢
- High Risk: > 150 mg/dL 🔴
▶️ VLDL:
More of portable fuel trucks is indirectly saying more portable fuel is produced.
Hence It is not directly measured, but estimated as 20% of triglycerides
- VLDL < 20 mg/dL 🟢
▶️ LDL-C
More unused bricks in circulation is a concern as more delivery trucks can cause a traffic jam (plaque)
- Ideal: < 130 mg/dL 🟢
- High Risk: > 160 mg/dL 🔴
▶️ Lp(a):
The more unused bricks in circulation especially inside those trucks with sticky tired is a big cause of concern. But it’s not under your control.
- Optimal: < 20 🟢
- SubOptimal: 20- 50🟡
- High risk: 50- 100🟠
- Very high risk > 100🔴
▶️ ApoB:
You want less of trucks with these license plate on the road. They are either carrying unused bricks or extra portable fuel, either way not good.
- Optimal: < 80 mg/dL (high risk patients)
: < 90 mg/dL (general population) 🟢
- High: > 120 mg/dL 🔴
▶️ ApoA1:
You want more of cleanup trucks with these license plate on the road.
- Optimal: < 0.6 🟢
- Acceptable: < 0.8 🟡
- High risk: > 0.9 (men), > 0.8 (women) 🔴
▶️ ApoB / ApoA1 Ratio:
This ratio reflects the balance between Delivery trucks & Clean up trucks. More clean up trucks is always better
- Optimal: < 0.6 🟢
- Acceptable: < 0.8 🟡
- High risk: > 0.9 (men), > 0.8 (women) 🔴
▶️ Triglycerides / HDL Ratio:
This ratio reflects the balance between large Cargo trucks specifically & Clean up trucks. Again more clean up trucks & less portable fuel on the road is always better
- Excellent: < 1 🟢
- Good: < 2 🟡
- At risk: > 2 🟠
- High risk: > 4 🔴
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3 types of hunger explained "simply"
Hunger isn’t just about an empty stomach. Your brain receives signals from body composition, hormones, emotions, and even gut microbes. Here’s how the three major types work:
1️⃣ Homeostatic Hunger (Energy Balance Hunger)
This is your body’s “fuel gauge.” It rises and falls based on energy needs and metabolic signals.
What drives it: Ghrelin from the stomach stimulates hunger; leptin from fat cells and incretin hormones (GLP-1, PYY, CCK) reduce it.
What it does: Ensures your intake matches your energy needs for exercise, growth, and tissue repair.
🟢 Example: After a long run, homeostatic hunger pushes you to replace calories and glycogen.
2️⃣ Hedonic Hunger (Reward-Driven Hunger)
This is your “food pleasure” system. It’s triggered by sight, smell, habits, and emotions, not by actual energy needs.
What drives it: Brain reward circuits activated by highly palatable foods (sugar, fat, salt).
What it does: Encourages eating even when you’re not truly hungry. Weak satiety signals make it harder to stop.
🟢 Example: Craving dessert after dinner even though you’re full.
3️⃣ Microbiota-Driven Hunger (Gut Microbe Hunger)
Your gut bacteria also shape hunger signals by producing metabolites that influence hormones and the brain.
What drives it: Microbes generate compounds that mimic hunger or satiety signals, affect insulin, and modulate ghrelin, GLP-1, and PYY.
What it does: Links gut health to appetite regulation and metabolic control.
🟢 Example: Certain bacterial imbalances may increase cravings or weaken satiety, nudging overeating.
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A comprehensive overview of the different types of antibodies (Immunoglobulins - Ig), their structure, location, and special features.
pin.it/5uKsGcGQ7
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Vitamin B12 absorption can be viewed as a biochemical obstacle course
Here’s the shortcut to how your body actually gets B12 from food in 7️⃣ steps:
1️⃣ Starts in Food
Meat, eggs, dairy, fish → B12 is protein-bound.
💡 Example: That salmon fillet carries B12, but it’s locked up tight.
2️⃣ Stomach Acid Breaks It Free
Gastric acid + pepsin release B12 from food proteins.
💡 Without stomach acid (think antacids or age-related decline), B12 release suffers.
3️⃣ Haptocorrin (HC) Grabs It First
In the stomach, B12 binds to HC (a protective chaperone).
💡 This shields B12 from the harsh acidic environment.
4️⃣ Intrinsic Factor (IF) Takes Over
In the small intestine, enzymes break HC → B12 rebinds to IF (made by stomach cells).
💡 No IF = no absorption (that’s what happens in pernicious anemia).
5️⃣ Absorption in the Ileum
The B12–IF complex docks on special receptors (Cubam) in the ileum.
💡 That’s why B12 deficiency can occur after ileum surgery or Crohn’s disease.
6️⃣ Transport in Bloodstream
Once inside, B12 switches to transcobalamin (TC), the form cells can use.
💡 B12 + TC = delivery service to tissues and mitochondria.
7️⃣ Cellular Activation
Inside cells, B12 converts to active forms:
Methylcobalamin → makes methionine (DNA + neurotransmitters).
Adenosylcobalamin → runs mitochondria (energy).
💡 No active B12 = fatigue, neuropathy, brain fog.
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An elegant infographic that illustrates the complex pathways by which gut microbiota influence brain function, immune modulation, and whole-body metabolism via the gut–brain axis.
🧠At the foundation, microbial metabolites [including short-chain fatty acids (SCFAs), bile acids, endocannabinoids, and microbial-associated molecular patterns (PAMPs)] interact with intestinal epithelial and immune cell receptors such as TLRs, TRPV1, CB1/CB2, TGR5, GPRs, and nuclear receptors. These interactions regulate gene expression, immune signaling, hormone release (e.g., GLP-1, PYY), and neurotransmitter production (e.g., serotonin, GABA).
Metabolites and signaling molecules enter portal circulation, influencing cell energy metabolism, intestinal gluconeogenesis, barrier integrity, and mucosal immunity. Neural communication occurs through the enteric nervous system (ENS) and the vagus nerve, enhancing gut motility and secretions.
Upstream effects extend to the brain, impacting neuronal function, neurogenesis, cognitive performance, memory, and blood–brain barrier integrity, while reducing inflammation in microglia and astrocytes. Systemic metabolic outcomes include improved insulin sensitivity, enhanced AMPK activity, reduced gluconeogenesis, and decreased lipid storage.
This figure highlights the intricate bidirectional communication between the gut microbiome and host physiology, demonstrating how microbial metabolites and signaling cascades integrate to regulate health, inflammation, and neuroendocrine function.
frontiersin.org/journals/end…
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Visceral fat is the most dangerous fat in your body.
It wraps around your organs, slows your metabolism, and silently fuels disease.
Here are 9 science-backed habits to shrink it naturally: 🧵
1. Stop eating late
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💢Distribución de líquidos intravenosos después de la infusión
#ENARM_INTENSIVO #ESTUDIA_MEDICINA
