Your Most Common Health Questions — Answered Without the Fluff

Q: How much vitamin D do I actually need?

The official EU reference intake for vitamin D is 15 µg (600 IU) per day for adults, but many researchers and clinicians argue this is the minimum to prevent deficiency rather than a target for optimal health. Studies on immune function, bone health, and mood consistently use doses in the 1,000–4,000 IU range.

Deficiency is genuinely widespread — particularly in Northern Europe, where sunlight exposure is insufficient for endogenous production for much of the year. The best way to know your status is to test it. A blood test measuring 25(OH)D will give you your actual level. Most functional medicine practitioners consider 75–150 nmol/L to be optimal.

Q: Does intermittent fasting actually work?

Intermittent fasting (IF) — primarily 16:8 time-restricted eating or 5:2 protocols — has a solid evidence base for metabolic health. It reliably improves insulin sensitivity, reduces fasting glucose, and can lower inflammatory markers. The weight loss benefit, however, appears to be primarily a function of reduced total calorie intake rather than anything unique to the fasting window itself.

For people who find it easier to manage appetite by skipping breakfast or compressing eating into a window, IF is a practical and effective approach. For people who feel better with morning meals and regular eating patterns, the same metabolic benefits can be achieved through food quality and portion management.

The evidence does not support intermittent fasting as superior to other well-structured dietary approaches — but it is a legitimate tool that works well for many people.

Q: What drives chronic inflammation and how can diet help?

Chronic low-grade inflammation is increasingly understood as an underlying driver of cardiovascular disease, type 2 diabetes, cognitive decline, and autoimmune conditions. Unlike acute inflammation (which is part of healing), chronic inflammation is systemic and often silent.

The main dietary contributors to chronic inflammation:

• Excess refined carbohydrates and ultra-processed foods
• High omega-6 to omega-3 ratio (from seed oils and low oily fish intake)
• Excess sugar, particularly fructose in processed form
• Chronic alcohol consumption
• Insufficient antioxidant intake (low vegetable and fruit variety)

The most consistently anti-inflammatory dietary patterns share several features:

• High variety of colourful vegetables and fruits (diverse polyphenols)
• Regular oily fish or algae-based omega-3 supplementation
• Adequate fibre to support gut microbiome diversity
• Minimally processed whole foods as the base
• Moderate and consistent physical activity (a powerful anti-inflammatory intervention)

Q: When do electrolytes actually matter?

Electrolytes — primarily sodium, potassium, magnesium, and chloride — are dissolved minerals that carry electrical charge in your body. They regulate fluid balance, nerve signalling, muscle contraction, and pH.

For most healthy adults eating a reasonable diet, electrolyte supplementation is unnecessary in daily life. They become genuinely important in specific contexts:

• Prolonged exercise (60+ minutes of sweating), particularly in heat
• Low-carbohydrate or ketogenic diets, which cause increased sodium and potassium excretion
• Hot climates where sweat losses are high throughout the day
• Gastrointestinal illness causing significant fluid and electrolyte loss

For casual gym sessions or everyday activity, plain water and a balanced diet provide adequate electrolytes for the vast majority of people. The electrolyte drink industry has done an effective job of creating demand where little actually exists.

Q: Why is magnesium deficiency so common?

Magnesium is involved in over 300 enzymatic reactions in the body, yet studies consistently show that a significant portion of the population in Western countries consumes less than the recommended intake. Several factors explain this:

• Declining magnesium content in soils (and therefore in crops) over the past 50 years
• Low consumption of the best dietary sources: dark leafy greens, legumes, nuts, and whole grains
• High consumption of refined and ultra-processed foods with low mineral density
• Increased loss through urine due to stress (cortisol increases urinary magnesium excretion) and alcohol

Symptoms of suboptimal magnesium include muscle cramps, poor sleep quality, fatigue, and increased anxiety. These are non-specific enough that magnesium deficiency often goes unrecognised.

Supplemental forms vary in bioavailability: magnesium glycinate and malate tend to be well-absorbed; magnesium oxide is cheap but poorly absorbed. If sleep or muscle recovery is your primary goal, glycinate is the most studied form for these applications.

Q: What does my gut microbiome actually need?

The gut microbiome — the trillions of bacteria, fungi, and other microorganisms in your digestive tract — is closely linked to immune function, mood, metabolic health, and inflammation. Research in this area has expanded rapidly, and while some specifics remain under investigation, several principles are well-established.

What consistently supports a healthy, diverse microbiome:

This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider before starting any new supplement regimen, especially if you take medication or have an existing health condition.