Should a 70 year old woman take vitamin C?

At 70, a woman's recommended vitamin C intake is exactly what it was at 30: 75mg a day.

That surprises most people. The assumption runs the other way — that ageing bodies absorb less and need more. When researchers tested it in 2,828 US adults who took no supplements, the picture turned out to be conditional rather than age-driven.

What changes after 70 is not the requirement. It is how much slack you have if your intake falls short.

What This Article Covers

• The short answer
• What changes after 70, and what doesn't
• Why the national data looks contradictory
• The part of the question that is specifically female
• When the answer is yes
• Safety, kidneys and medications
• If you do supplement: the absorption question
• Bio Absorb Nutraceuticals Liposomal Vitamin C
• Frequently asked questions
• Conclusion
• Research references

The Short Answer

For a healthy 70-year-old woman eating a reasonable diet, there is no strong case that age by itself creates a need to supplement. The 2023 analysis of NHANES 2017–2018 data put it plainly: healthy ageing in people living independently does not increase vitamin C requirements. The US RDA of 75mg a day for women applies at 70 exactly as it does at 30.

The case changes when intake is low. In that same cohort of 2,828 adults, the median vitamin C intake was only 53mg a day — well under the 75mg target. At intakes below 75mg, older adults showed significantly lower blood levels than younger adults eating the same amount. Above 75mg, the difference disappeared.

So the honest answer is conditional. It depends far more on what she eats, what conditions she lives with and what medications she takes than on the number of candles on the cake.

What Changes After 70, and What Doesn't

Three things genuinely shift with age, and none of them is the RDA.

The first is tolerance for a low intake. Older non-smokers in the NHANES analysis needed roughly 93mg a day (range 78–112) to reach an adequate blood level of 50 µmol/L, against about 67mg (53–82) in adults aged 18 to 36. The target is the same; the margin for error is thinner.

The second is the weight of accumulated exposure. Older smokers in the cohort had smoked for a median of 46 years, against 11 years in the younger group, and needed more than 183mg a day to reach the same adequate level. That is more than double the extra 35mg a day the RDA adds for smokers, which is the background to why smokers need more vitamin C than non-smokers.

The third is chronic illness. Among the older adults eating under 75mg a day, 30% had diabetes and 12% had experienced a stroke, against 22% and 5% among those eating more. Illness and low intake travel together, and both pull status down.

• Requirement at 70: unchanged at 75mg a day for women
• Intake needed to reach adequacy if status is low: roughly 93mg against 67mg in young adults
• Intake needed by an older long-term smoker: in excess of 183mg a day
• Median intake of the whole 2,828-person cohort: 53mg a day

Why the National Data Looks Contradictory

Two analyses of the same survey appear to disagree, and the disagreement is worth understanding because it contains the actual answer.

One reading of NHANES 2017–2018 found adults aged 60 and over averaging 8 µmol/L higher than those aged 20 to 59 — older adults doing better, not worse. The other found older adults significantly lower. Same survey, same two years.

The difference is supplement use. The first analysis included people taking supplements, and the rise it detected was concentrated in older women, apparently driven mainly by their higher supplement use. The second analysis excluded all 2,828 participants who supplemented and found the opposite.

Read together, they say something more useful than either does alone. Older women who supplement generally look fine in the national data. Older women who do not, and whose diet sits under 75mg a day, are the group sitting lower than younger adults on an identical intake.

The Part of the Question That Is Specifically Female

Being a woman changes the arithmetic in three small ways. None of them argues for a higher intake at 70, but all three are worth knowing.

The first is the RDA itself. Women are advised to get 75mg a day against 90mg for men. Most national recommendations, as a 2020 review of global RDA criteria points out, derive the female figure by scaling down from the body weight of a 70kg man rather than from data collected in women.

The second cuts against expectation. In the NHANES cohort, women had a median blood vitamin C of 47 µmol/L against 39 µmol/L in men, despite near-identical intakes of 52mg and 55mg a day. Women generally hold more vitamin C per unit of intake than men do.

The third is iron. After menopause, monthly iron losses stop, and vitamin C's well-documented ability to increase iron absorption shifts from a benefit toward a consideration — particularly for anyone with an iron-overload condition such as haemochromatosis. The mechanism itself is covered in how the vitamin C and iron pairing works.

When the Answer Is Yes

The research points consistently at circumstances rather than birthdays. A 2023 scoping review of comparative studies found limited evidence that healthy ageing on its own lowers vitamin C status, but found that institutionalised older people had both lower status and genuinely higher requirements, driven by low intakes and chronic illness that hospital and residential catering was not meeting.

That review also noted that nearly a quarter of the total global burden of disease falls on people aged 60 and over, which is the context in which the comorbidity signal matters. The circumstances that shift the answer toward yes are reasonably specific:

• A daily intake persistently below 75mg — the threshold where the age gap appears
• Living in residential or hospital care, where catering drove the clearest deficits in the review
• Current or long-term smoking, where older smokers needed over 183mg a day
• Chronic illness, notably diabetes, which was present in 30% of the low-intake older group
• A narrowed diet, poor appetite, dental problems or difficulty shopping and cooking

Low status is also associated with poorer scores in a 2017 systematic review of vitamin C and cognitive function, though association is not causation and no trial has shown that supplementing a well-nourished older woman improves cognition. The same caution applies to the signs of genuine deficiency, which are a different matter from sitting mid-range.

Safety, Kidneys and Medications

Vitamin C is water-soluble and well tolerated, but the ceiling matters more at 70 than at 30. The Tolerable Upper Intake Level is 2,000mg a day from all sources combined, above which gastrointestinal upset becomes common.

Three cautions deserve a conversation with a doctor or pharmacist rather than a decision made alone. Reduced kidney function is common with age, and high intakes raise urinary oxalate and kidney-stone risk. Iron-overload conditions sit awkwardly with vitamin C's effect on iron absorption. And vitamin C can interact with statins, niacin and with chemotherapy and radiotherapy, which matters in a population where multiple prescriptions are the norm.

Dose size also has diminishing returns. The landmark NIH depletion–repletion study found absorption complete for a single 200mg dose but falling to roughly 33% at 1,250mg, so one large daily dose is an inefficient way to raise status at any age. Whether 1,000mg is too much is covered separately.

If You Do Supplement: The Absorption Question

If supplementing is the right call, the delivery form is a reasonable question, because standard vitamin C absorbs poorly at the doses people actually take. A 2025 scoping review of 10 clinical trials found that 9 showed higher bioavailability for liposomal vitamin C, with peak concentrations 1.2 to 5.4 times higher and total exposure 1.3 to 7.2 times higher than non-liposomal forms.

That spread of 1.3 to 7.2 is wide, and the honest reading is that the absorption advantage is established while the size of it varies by formulation and by how depleted the person was to begin with. What has not been shown is a clinical outcome advantage. No trial has tested whether better-absorbed vitamin C produces better health outcomes in older women specifically, and that gap should be stated rather than glossed over. The full picture of how liposomal delivery works sets out both sides.

Practical factors often matter more than the pharmacokinetics at this age. A liquid suits anyone who finds capsules hard to swallow or who is already managing several daily tablets; capsules suit anyone who travels or wants no refrigeration. Whether it is reasonable to take it every day is a separate and commonly asked question.

Bio Absorb Nutraceuticals Liposomal Vitamin C

Bio Absorb Nutraceuticals makes its liposomal vitamin C in two formats, which is the relevant distinction for an older reader rather than anything about the formulation itself.

The Liposomal Vitamin C Liquid 1000mg (Corn-Free) mixes into water or juice, which removes the swallowing problem entirely and makes it straightforward to split an intake across the day rather than take it all at once. The Liposomal Vitamin C Capsules 1000mg (Corn-Free) need no refrigeration and travel without fuss.

Both are verified corn-free, non-GMO, gluten-free, nut-free and vegan, made in a GMP-certified Canadian facility and third-party tested every batch. The corn-free verification is not a marketing flourish: most commercial ascorbic acid is fermented from corn, which matters to anyone managing a corn sensitivity alongside other dietary restrictions. Both carry a money-back guarantee.

For the current specification of either format, including serving details and pricing, see the liquid product page or the capsule product page. Neither product, and no supplement, substitutes for a conversation with the doctor or pharmacist who knows your medication list.

Frequently Asked Questions

How much vitamin C should a 70-year-old woman take?

The recommended intake is 75mg a day, the same as for any woman aged 19 or over, with no separate allowance for older adults. If blood levels are already low, reaching an adequate 50 µmol/L took around 93mg a day in older non-smokers, against 67mg in young adults. The ceiling for all sources combined is 2,000mg a day.

Do older adults absorb vitamin C less well?

Not straightforwardly. Pharmacokinetic work in women, including a 1990 depletion–repletion study of age and vitamin C disposition in females, found no significant age difference in absorption or clearance — but the participants were healthy non-smokers whose status likely resembled the higher-intake group. The age gap in the 2023 data appeared only below 75mg a day.

Does any country recommend more vitamin C for older people?

One. France set a reference value of 120mg a day for adults aged 75 and over in 2001, on precautionary grounds relating to immunity, cardiovascular risk, cancer risk and cognition. It is a policy judgement rather than a demonstrated outcome, and no other national authority has followed it.

Should a 70-year-old woman take vitamin C if she already eats well?

If her intake is comfortably above 75mg a day — roughly a kiwifruit and half a cup of red pepper — the 2023 data suggest she converts it to blood vitamin C no less efficiently than a 30-year-old. The group that showed a measurable shortfall was the one eating under 75mg a day.

Is liposomal vitamin C better for older women?

For absorption, the 2025 review of 10 trials found 9 showing higher bioavailability, with total exposure 1.3 to 7.2 times higher. For health outcomes in older women specifically, no trial has tested it, so the honest answer is that the absorption advantage is established and the outcome advantage is unstudied.

What should she check with a doctor first?

Kidney function and any history of kidney stones, iron-overload conditions such as haemochromatosis, and her full medication list, since vitamin C can interact with statins, niacin and cancer treatments. These matter more than age itself, and more at 70 than at 30 because multiple prescriptions are more common.

Conclusion

Age is not the reason a 70-year-old woman would take vitamin C. Diet, illness, smoking and living circumstances are, and the 75mg-a-day threshold is where the research says the question starts to matter.

If supplementing is the answer in your case, and your doctor agrees it fits with your medications, see the current serving details for Bio Absorb Nutraceuticals Liposomal Vitamin C.

Research References

1. Does Aging Affect Vitamin C Status Relative to Intake? Findings from NHANES 2017–2018. Nutrients, Vol. 15, Issue 4, Article 892 (2023). Analysis of 2,828 non-supplementing US adults; source of the 75mg threshold, the 93mg and 67mg adequacy intakes, the 183mg figure for older smokers, the 47 against 39 µmol/L sex difference, and the diabetes and stroke prevalence figures.
2. Does Aging Have an Impact on Vitamin C Status and Requirements? A Scoping Review of Comparative Studies of Aging and Institutionalisation. Nutrients, Vol. 15, Issue 4, Article 915 (2023). Finds limited evidence that healthy ageing lowers status, and clear deficits among institutionalised older people.
3. Do Liposomal Vitamin C Formulations Have Improved Bioavailability? A Scoping Review Identifying Future Research Directions. Basic & Clinical Pharmacology & Toxicology (2025). Ten trials; nine showed higher bioavailability, with Cmax 1.2–5.4-fold and AUC 1.3–7.2-fold higher.
4. Vitamin C Status of US Adults Assessed as Part of the National Health and Nutrition Examination Survey Remained Unchanged between 2003–2006 and 2017–2018. The Journal of Applied Laboratory Medicine, Vol. 8, Issue 2 (2023). Source of the 8 µmol/L higher reading in adults aged 60 and over, which included supplement users.
5. Discrepancies in Global Vitamin C Recommendations: A Review of RDA Criteria and Underlying Health Perspectives. Critical Reviews in Food Science and Nutrition, Vol. 61 (2020), pp. 742–755. Source of the French 120mg reference value for ages 75 and over and of the isometric scaling critique.
6. Vitamin C Pharmacokinetics in Healthy Volunteers: Evidence for a Recommended Dietary Allowance. Proceedings of the National Academy of Sciences USA, Vol. 93, Issue 8 (1996). Depletion–repletion study establishing complete bioavailability at a single 200mg dose and roughly 33% at 1,250mg.
7. Effects of Age and Intake on Vitamin C Disposition in Females. European Journal of Clinical Nutrition, Vol. 44 (1990), pp. 447–460. Found no significant age difference in vitamin C pharmacokinetics in healthy non-smoking women.
8. Vitamin C Status and Cognitive Function: A Systematic Review. Nutrients, Vol. 9, Article 960 (2017). Reports association between vitamin C status and cognitive measures; does not establish causation.
9. Vitamin C — Health Professional Fact Sheet. National Institutes of Health, Office of Dietary Supplements. Source of the 75mg and 90mg RDAs, the 2,000mg Tolerable Upper Intake Level, the additional 35mg for smokers, and the medication and iron-overload cautions.

About the Author

David Kimbell is a health writer, digital entrepreneur and former aerospace engineer, based in Ottawa, Canada. He loves translating complex science into clear, actionable guidance for consumers seeking evidence-based solutions.

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Important Disclaimers

Medical Disclaimer: This article provides educational information only and is not intended as medical advice. Always consult a qualified healthcare professional before starting any supplement, particularly if you have a medical condition, take prescription medication, or are pregnant or breastfeeding.

Regulatory Disclaimer: These statements have not been evaluated by the Food and Drug Administration or Health Canada. This product is not intended to diagnose, treat, cure or prevent any disease.