Sunday Natural’s KSM-66 Royal is a clean-label capsule, but a Shoden capsule can carry more withanolides. The difference per capsule is about 1.7 times, not 7 times. No trial has compared the two extracts head to head.
Ashwagandha also has a real safety record. Read the safety section before you buy any brand.
What is the difference between Sunday Natural KSM-66 and Shoden?
It comes down to how much withanolide is in each capsule. Withanolides are the compounds these extracts are standardized to.
| If you compare | KSM-66 (Sunday Natural Royal) | Shoden (HSN Strong) |
|---|---|---|
| Extract per capsule | 500 mg | 120 mg |
| Labelled withanolide share | 5% | 35% |
| Withanolides per capsule | 25 mg | 42 mg |
Shoden is 7 times more concentrated. But a Shoden capsule holds far less extract. So per capsule you get about 1.7 times the withanolides (42 divided by 25), not 7 times.
A higher withanolide number doesn’t prove a stronger effect. No trial compares Shoden with KSM-66 directly, so neither can be called the better extract.
Does ashwagandha work for stress?
Small trials say it lowers stress scores, and the evidence is weak.
A 2024 meta-analysis pooled nine randomized trials with 558 people. Ashwagandha lowered Perceived Stress Scale scores, Hamilton anxiety scores and serum cortisol compared with placebo. Four of the trials reported mild to moderate side effects. The authors say longer-term safety is unknown (Arumugam et al., 2024).
A 2022 meta-analysis of 12 trials found the same direction. It rated the certainty of the evidence as low for both stress and anxiety (Akhgarjand et al., 2022).
Those trials used many different extracts. They don’t tell you which brand works.
Is ashwagandha safe for your liver?
It can injure the liver in some people. It’s rare, but it happens.
- A case series from Iceland and the US Drug-Induced Liver Injury Network described five people with ashwagandha-linked liver injury. Jaundice began 2 to 12 weeks after they started. Liver tests normalized within 1 to 5 months in four of them. One was lost to follow-up (Björnsson et al., 2020).
- A 2026 scoping review covered 25 patients in 13 publications. Most recovered after stopping. One needed a liver transplant for acute liver failure. Three people with existing cirrhosis died after decompensation (McIntyre et al., 2026).
- A 2026 review lists ashwagandha among newly recognized liver-toxic herbal supplements (Björnsson, 2026).
Stop and see a doctor if you get yellow skin or eyes, itching, nausea or unusual tiredness. If you have liver disease, skip it.
Is ashwagandha banned anywhere?
Regulators have acted in several places.
- Denmark has a total ban on ashwagandha in food supplements.
- In spring 2024 the Dutch national health institute advised against use, citing toxicity and hormone-interaction concerns.
- Australia’s TGA introduced a mandatory pregnancy warning in 2020.
- The UK Food Standards Agency opened a call for evidence in July 2024 to decide whether a ban is needed.
- EU regulators are weighing an Article 8 review, and no decision has been reported.
Source: NutraIngredients regulatory timeline.
Who should avoid ashwagandha?
- Anyone who is pregnant. Australia’s TGA introduced a pregnancy warning for it.
- Anyone with liver disease.
- Anyone with a thyroid condition. A Dutch case report describes thyrotoxicosis in a healthy woman after she raised her dose. It resolved after she stopped (van der Hooft et al., 2005). A small trial in subclinical hypothyroidism went the other way and moved thyroid values toward normal, so the effect on the thyroid is not settled (Sharma et al., 2018).
- Anyone on prescription medicine. Ask your doctor or pharmacist first.
Is Sunday Natural worth the price?
Sunday Natural’s KSM-66 Royal has 500 mg of extract and 25 mg of withanolides per capsule. Check the price per milligram of withanolides, not per bottle.
Shoden gives you more withanolides per capsule. For stress, the trials above don’t separate the two extracts.
Questions
Is Shoden stronger than KSM-66?
Shoden is labelled 35% withanolides and KSM-66 5%. Per capsule that’s about 42 mg versus 25 mg in the products compared here. No trial has tested one against the other.
Does ashwagandha lower cortisol?
A 2024 meta-analysis of nine trials found lower serum cortisol than placebo. The evidence is limited and the extracts varied.
Can ashwagandha damage your liver?
Yes, in rare cases. Most people recover after stopping. A few have needed a transplant or died.
Is ashwagandha safe in pregnancy?
Avoid it. Australia’s TGA introduced a mandatory pregnancy warning in 2020.
Should you take ashwagandha with a thyroid condition?
Talk to your doctor first. Case reports and a small trial point in different directions.