Are You Taking Too Many Vitamins? The Signs Most People Miss

The S&P 500 crossed 7,600 for the first time. Chips surged. Alphabet sold $80 billion in stock.

The quick scan: Tuesday delivered another set of records, quiet on the surface and eventful underneath. The S&P 500 crossed 7,600 for the first time in its history. The NASDAQ and Dow followed with their own record closes. The chip complex led again. Alphabet was the session's big decliner, dropping nearly 4% after announcing an $80 billion stock sale – one of the largest equity offerings in history – to fund AI infrastructure expansion.

S&P 500: +0.13%, 7,609.78 – First close above 7,600; utilities and tech led, with just four sectors in the red
Dow Jones: +0.45%, 51,307.79 – Added 228 points; Broadcom, Chevron and Goldman Sachs led gains while Alphabet weighed
NASDAQ: +0.03%, 27,093.90 – Essentially flat but a record nonetheless; Broadcom (+5%) ahead of earnings offset Alphabet's decline.

What's driving it: The AI infrastructure trade is doing two things simultaneously. It's lifting chip stocks to new highs – Broadcom, Marvell, and Nvidia all gained – while also triggering the kind of capital raises that remind investors how expensive building the future actually is. Alphabet's $80 billion offering, which includes a $10 billion investment from Berkshire Hathaway, is the clearest signal yet that the hyperscalers are spending at a scale that requires external capital. The Iran situation remained an impasse – talks suspended after Israel's actions in Lebanon, though Trump said negotiations were continuing at a "rapid pace." Oil slid modestly. The Russell 2000 small-cap index was the real standout, gaining 0.9% on the day, suggesting the rally is beginning to broaden beyond mega-cap tech.

Bottom line: A first close above 7,600, an $80 billion AI stock sale, and the small-cap index outperforming – Tuesday had something for everyone. For L-Plate Retirees, the Alphabet offering is a useful data point: AI enthusiasm is real, but the capital requirements are extraordinary, and those requirements will eventually show up somewhere in earnings. For now, the market is absorbing it comfortably.

Your Supplement Routine Might Be Doing More Harm Than You Think

The scoop: "Many people assume vitamins taken in excess will just be 'expensive pee' – that our body dumps the extra vitamins like a magic filter," says Dr Liz Daniels, a physician and registered dietitian. "But this is not always the case." Bodies can absorb vitamins beyond necessary thresholds, with real and serious consequences.

A multivitamin, a vitamin D capsule, a B12 for energy, magnesium for sleep, calcium for bone density – each individually reasonable. Add fortified cereal, enriched protein powder, and an energy drink, and total daily intake of certain nutrients climbs well above recommended levels without anyone noticing. Here, three medical experts outline the four warning signs – and how to supplement more safely.

Sign 1: Gastrointestinal distress

Nausea, vomiting, constipation, or stomach pain are often the first sign that something in the supplement stack is off.

Fat-soluble vitamins – A and D in particular – can reach toxic levels and cause nausea and stomach pain, explains Dr Oluwatosin Ajao, who is board-certified in internal medicine, lifestyle medicine and obesity medicine. "Excess iron can upset your stomach and even harm the liver if taken in very high amounts."

Vitamin C and magnesium are also frequent culprits, according to Daniels. High doses of vitamin C taken at once can cause abdominal cramping and diarrhoea. Magnesium oxide specifically – one of the most commonly sold forms – can cause watery diarrhoea within hours of taking it.

GI symptoms are easy to attribute to something else – a meal, a passing bug, stress. If they're recurring and you're on supplements, the stack is the first thing to examine.

Sign 2: Numbness and tingling

Taking too much vitamin B6 can damage nerves, leading to numbness or tingling in the hands and feet. At high doses over long periods, it can progress to difficulty walking or maintaining balance. "Any nerve damage from consuming B6 in excess may persist, even when you stop taking the supplement," says Ajao.

B6 is added to a wide range of products – supplements, beverages, and energy drinks in particular – making it easy to consume significantly more than intended without any individual product looking like the problem. The dose that causes nerve damage isn't typically a single massive supplement; it's the quiet compounding of multiple moderate sources over months or years.

Sign 3: Extreme thirst, frequent urination, and kidney stones

This cluster of symptoms points specifically to vitamin D, and it works through a chain of effects that's worth understanding.

Excess vitamin D raises blood calcium levels by promoting greater calcium reabsorption from the gut. Elevated calcium then increases thirst and urination frequency. Over time, too much circulating calcium also increases the risk of developing kidney stones.

"While excessive circulating calcium contributes to these health effects, it's the high vitamin D supplementation that initiates this cascade," explains Ajao.

Vitamin D has been one of the most aggressively marketed supplements of the past decade, and high-dose supplementation has become relatively common. The Endocrine Society updated its vitamin D guidelines in 2024; the central message is that a medically supervised, individualised approach is considerably safer than a standard over-the-counter dose taken indefinitely without blood-test monitoring.

Sign 4: Hair loss

Vitamin A, taken in excess over time, can disrupt the normal hair growth cycle.

"Taking too much vitamin A over time can lead to hair loss," explains Ajao. Vitamin A has what she describes as a Goldilocks role in hair health – you need some to support it, but too much interferes with the signalling systems necessary for healthy growth and shrinks the oil-producing glands in the scalp, creating an environment that discourages hair follicles from functioning normally.

Because vitamin A is fat-soluble and stored in body tissues, it accumulates gradually. Liver damage, bone weakness, and joint pain are among the longer-term consequences of sustained excess, with hair loss appearing as one of the earlier signals that something is off.

How to supplement more safely

The experts suggest four practical steps for anyone who takes supplements regularly.

Check your prescriptions. Vitamins interact with medications in ways most people don't anticipate. Vitamin K can influence blood thinners like warfarin; excess vitamin E may raise bleeding risks with some medications; high folic acid levels can mask signs of vitamin B12 deficiency. Running your supplement list past a physician is not optional – it's the most important safety check in the routine.

Don't take more than the recommended amount. "Experts have set safe daily limits for vitamins and minerals," says Ajao. "Taking more than these amounts can be harmful." Excess can also affect levels of other essential nutrients, creating secondary deficiencies that weren't there to begin with.

Treat vitamins with the same caution as prescriptions. "Extra vitamins may not improve health and can even cause serious side effects," says Ajao.

Consult a health care provider before starting anything new. Supplements carry a cultural assumption of being inherently safe. They are not.

The bigger picture

Daniels offers what is perhaps the most useful reframe: "Most vitamins and minerals cannot be accurately tested through the bloodstream, and diagnosis can be tricky, so the most important way to know if you're getting too much is to look closely at your diet and supplement use."

The supplement stack that made sense five years ago may not reflect what your diet actually provides today. Fortified foods are more prevalent than they were a decade ago. Food habits change. Medication interactions evolve. An annual review of what you're taking and why – with a healthcare provider who knows your full picture – is the kind of low-cost maintenance most people defer indefinitely.

"The best way to get vitamins is to eat a healthy, balanced diet," says Ajao. "Most people who eat well do not need to take a daily vitamin or supplement." For those who do benefit from targeted supplementation, the goal is to fill a specific, documented gap – not to optimise every function simultaneously.

More is not always better. Sometimes it's quietly worse.

Actionable Takeaways for L-Plate Retirees

• Know which of your supplements are fat-soluble. Vitamins A, D, E and K accumulate in body tissues and can reach toxic levels over time. Vitamins C and B (except B6 at high doses) are excreted. Apply significantly more caution to the fat-soluble group, and don't take them indefinitely without blood-test monitoring.

• Take GI symptoms seriously if you're on supplements. Nausea, stomach pain, constipation, or recurring diarrhoea alongside a supplement routine is worth flagging to a doctor before assuming it's something else. The supplement stack is the first thing to examine.

• Be specifically alert to B6 accumulation. Check how many products in your daily routine contain B6 – supplements, energy drinks, fortified foods. Nerve symptoms (numbness, tingling, balance issues) that develop gradually and don't resolve when supplementation stops deserve prompt medical attention.

• Monitor vitamin D with blood tests, not feelings. Vitamin D deficiency and excess can both be asymptomatic for long periods. Supplementing without knowing your current blood level is guesswork. Get tested, dose to your specific result, and retest annually.

• Run your supplement list past whoever manages your prescriptions. Vitamin K and warfarin, vitamin E and blood thinners, folic acid and B12 – these interactions are real and underappreciated. This check takes five minutes and can prevent a serious problem.

• Review the full supplement routine annually. What was appropriate at 55 may not be appropriate at 65. Body composition, absorption rates, dietary habits, and medication lists all change. An annual review with a healthcare provider keeps the routine calibrated to your actual current needs.

Your Turn:
Before reading today's issue, did you think of your supplement routine as something that could cause harm – or has it felt essentially risk-free because vitamins are "natural"?
The article points out that most vitamins can't be accurately tested through blood tests, making diet and supplement auditing the most important diagnostic tool. When did you last look closely at every source of vitamins in your daily intake – food and supplements combined?
Of the four warning signs, is there one that you've experienced and attributed to something else? Looking back, does today's issue change how you'd interpret it?

👉 Hit reply and share your thoughts – your answers could inspire fellow readers in future issues.

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