Castile Soap Body Wash - Top Recipes and Best Practices
- The Humble Shepherd
- Mar 8, 2024
- 11 min read
Transform your skincare routine with Castile soap body wash – a gentle, plant-based alternative to many commercial washes that rely on stronger synthetic surfactants. Castile soap is usually made from olive oil or a blend of vegetable oils and water, without added detergents, and has been highlighted by dermatology sources as a mild yet effective cleanser that can be used on face, body and even hair when properly diluted, as outlined in this Cleveland Clinic guide to Castile soap. Its rich, creamy lather cleanses without aggressively stripping natural oils, making it a good candidate for daily use if you follow it with a moisturiser.
Because it’s biodegradable and free from many persistent surfactants, Castile soap also tends to be gentler on waterways than some synthetic cleaners; classic reviews on the biodegradability of soaps compared with synthetic surfactants and newer work on surfactants as emerging environmental pollutants both point to soap’s relatively rapid breakdown under typical wastewater conditions. In this guide, we’ll walk through top Castile body wash recipes and best practices so you can create simple, luxurious washes at home – and if you’d rather start with ready-made bars and liquids, you can always explore our Castile and olive-oil soap collection for an easy first step into a gentler routine.
Why Castile Soap Makes the Perfect Body Wash
Castile soap is a timeless choice for body wash because the formula is simple, plant-based and highly adaptable. Traditionally made from olive oil, modern versions often blend in coconut, hemp or jojoba oil for more lather and slip, while keeping to a base of biodegradable vegetable oils rather than petrochemical surfactants. That simplicity is part of the appeal for anyone trying to minimise potential irritants in the shower; consumer and clinical pieces alike note that milder, soap-based cleansers can work well for many people when paired with regular moisturising, even though very sensitive or eczematous skin may still prefer syndet (synthetic detergent) bars in some cases.
From a sustainability angle, Castile soap is also attractive. Classic research on soap and surfactant biodegradation and more recent reviews of synthetic surfactant pollution both emphasise that soaps made from natural fatty acids break down more readily than many synthetic surfactants, which can persist in wastewater and aquatic environments. For home use, the fact that Castile soap is sold as a concentrate means you can dilute it to suit your skin and local water hardness, then customise it with small amounts of glycerin, oils and essential oils – a topic we also explore in our broader guide to eco-friendly bath products in the UK.
Understanding Castile Soap Ingredients
Castile soap, renowned for its purity and simplicity, originates from the Castile region of Spain. Traditionally, this soap was crafted using just one key ingredient: olive oil. Rich in natural moisturisers, olive oil produces a gentle, creamy lather, making it ideal for sensitive skin. This single-plant oil foundation is what makes traditional Castile soap so pure and beloved in the world of traditional soap making.
Over time, modern variations have emerged, blending olive oil with other plant oils like coconut or hemp. Coconut oil, for instance, adds robust cleansing power and a fluffy, bubbly lather, while hemp oil contributes nourishing properties and a silky texture. These additions maintain the soap’s plant-based integrity while enhancing its performance.
The magic of Castile soap lies in the saponification process. Here, oils are combined with an alkali—usually sodium hydroxide for bar soap or potassium hydroxide for liquid soap. This reaction transforms oils into soap and glycerine, resulting in a product free from synthetic additives.
The name “Castile” reflects its heritage, but its enduring popularity stems from its natural, biodegradable ingredients. Whether made traditionally or with modern tweaks, Castile soap remains a beacon of pure, sustainable soap making, celebrated by those seeking a gentle yet effective cleanser.
Top DIY Castile Soap Body Wash Recipes
Classic Liquid Castile Body Wash
This timeless recipe is ideal if you’re new to Castile soap body washes and want something simple that still feels pampering.
Ingredients:
240 ml liquid Castile soap
240 ml distilled water
1 teaspoon vegetable glycerin (optional, for added moisture)
10 drops essential oil (for example, lavender for calm or tea tree for a fresher feel)
Instructions:
In a clean mixing bowl, combine the liquid Castile soap and distilled water. Stir gently to avoid creating excess foam.
Add the vegetable glycerin if you’d like extra slip and hydration. Glycerin is a well-studied humectant that helps attract and hold water in the outer skin layers, as shown in clinical work on glycerin-based moisturisers.
Stir in your chosen essential oil, keeping the total amount low to stay within typical leave-on and rinse-off safety ranges.
Transfer the mixture into a pump or foaming bottle using a funnel.
Benefits:
This base recipe is gentle, easy to customise and made from just a few ingredients. The Castile soap provides the cleansing action, while the optional glycerin improves hydration and post-wash comfort. For more ideas on pairing gentle cleansers with richer follow-up care, you can explore our article on moisturising bar soaps for dry skin.
Moisturising Honey and Castile Body Wash
Perfect for dry or winter skin, this recipe combines the gentle cleansing of Castile soap with the hydrating properties of honey and sweet almond oil. Honey has been investigated in dermatology as a topical ingredient with humectant, anti-inflammatory and wound-supporting properties, which helps explain why many people find it soothing in masks and washes, as summarised in reviews of honey in dermatology and skin care and honey’s role in wound-healing formulations. Almond oil, meanwhile, offers a light, emollient feel that suits dry or mature skin types.
Ingredients:
120 ml distilled water
120 ml distilled water
2 tbsp raw honey
1tbsp sweet almond oil
5 drops vanilla or orange essential oil for fragrance (optional)
Instructions:
In a mixing bowl, whisk together the liquid castile soap and distilled water.
Gradually add the raw honey, stirring to ensure it fully dissolves. Honey is a natural humectant, pulling moisture into the skin.
Add the sweet almond oil, which is rich in Vitamin E and deeply nourishing for dry skin.
If desired, stir in essential oil for a warm or uplifting scent.
Funnel the mixture into a pump bottle.
This body wash is deeply moisturising without being greasy. Honey soothes irritated skin, while almond oil helps restore softness and elasticity. Ideal for dry or sensitive skin. Store in a cool, dry place and use within 2 months.
Refreshing Citrus Castile Body Wash
Wake up your senses with this energising body wash, ideal for morning showers or hot summer days. The blend of citrus essential oils delivers a bright, uplifting scent while the Castile base handles the cleansing. Because some citrus oils can increase photosensitivity when left on the skin, they’re generally considered safer in rinse-off formats and when used at low concentrations, but it’s still wise to follow conservative essential oil usage guidelines and patch-test if you have reactive skin.
Ingredients:
1 tsp jojoba oil (for light hydration)
10 drops sweet orange essential oil
5 drops lemon essential oil
3 drops grapefruit essential oil
Instructions:
Combine the liquid castile soap and distilled water in a bowl, stirring gently.
Add the jojoba oil for a touch of hydration without greasiness.
Drop in the essential oils, mixing thoroughly to disperse the energising citrus fragrance evenly.
Use a funnel to transfer the mix into a bottle with a pump or squeeze top.
Citrus essential oils are naturally uplifting and help clarify the skin. This body wash is ideal for oily or combination skin, offering a fresh, clean feeling without stripping natural oils. Store in a cool, dark place to preserve the citrus oils and use within 3 months.
Sensitive Skin Gentle Formula
Designed with minimal ingredients for delicate skin, this soothing formula leans on chamomile and calendula for comfort. Chamomile has been studied for topical use and shows anti-inflammatory and antioxidant effects in both in vitro and clinical work, making it a popular choice in products for sensitive or reactive skin, as summarised in recent reviews of chamomile’s therapeutic applications and randomised studies of chamomile extracts. Calendula oil is often paired with chamomile in balms and creams for its traditional use in soothing redness and supporting barrier repair, making this combination a natural fit for a gentle body wash.
Ingredients:
240 ml unscented liquid castile soap
1 tbsp chamomile hydrosol (or steeped chamomile tea, cooled)
5 drops calendula oil (optional, for extra soothing properties)
Instructions:
In a clean bowl, mix the liquid castile soap and distilled water.
Stir in the chamomile hydrosol or tea. Chamomile is renowned for its anti-inflammatory and calming properties.
If desired, add calendula oil to further reduce redness and irritation.
Pour the mixture into a pump bottle using a funnel.
This gentle formula is perfect for sensitive or reactive skin. Chamomile calms the skin, while calendula oil supports healing. Unscented castile soap ensures no harsh fragrances. Store in a cool place and use within 2 months.
Best Practices for Using Castile Soap Body Wash
Castile soap body wash is a versatile, natural option, but it does behave differently from many conventional body washes. For most people, a dilution of roughly 1 part Castile soap to 3 parts water creates a pleasant, gentle cleanse; this is broadly in line with dilution suggestions from major brands such as Dr Bronner’s Castile soap dilution cheat sheet, which recommend using very small amounts for body washing and foaming pumps. Using distilled or filtered water helps improve stability, especially if your tap water is very hard. Mineral-rich water can interact with soap to form “soap scum” – insoluble mineral soaps that dull lather and leave residue – a process explained in more detail in resources on how hard water causes soap scum. Storing your diluted wash in amber glass protects both the soap and any essential oils from light, which can slow oxidation and extend freshness.
When applying, you can use a shower pouf to create a rich lather, which helps extend the product and provides a gentle exfoliation. Alternatively, using your hands offers a direct and simple approach, particularly for sensitive skin. Start with a small amount—approximately a teaspoon for the body—and adjust as needed.
Consider your water hardness: soft water produces more lather, while hard water may reduce bubbles and leave soap residue. If your water is hard, rinse thoroughly to prevent any lingering film.
For a luxurious experience, follow up with a natural moisturiser after your shower. This practice complements Castile soap’s cleansing properties, leaving skin refreshed and hydrated. By embracing these best practices, you’ll make the most of your Castile soap body wash.
Common Mistakes to Avoid
Using undiluted Castile soap straight from the bottle can feel harsh or drying for some people, especially if your skin is already sensitive or if you’re using strong essential oil blends. Always dilute according to your recipe or the manufacturer’s guidance, and remember that more soap isn’t always better: dermatology-focused explainers on surfactants in cosmetic and cleaning products and consumer articles on soaps vs cleansers both point out that over-cleansing and high-foaming formulas can disrupt the skin barrier and increase dryness. Aim for a silky feel and comfortable rinse-off, adjusting your dilution and add-ins until your skin feels clean but not tight.
Hard water can cause soap scum, leaving residue in sinks and reducing lather. Minerals in hard water react with soap, forming insoluble salts. To avoid this, use distilled or filtered water for dilution. If hard water is unavoidable, consider adding a chelating agent like citric acid (1 tsp per litre) to bind minerals.
Over-diluting soap leads to ineffective cleaning and weak lather. Liquid soap should feel silky and produce a good foam. If it’s watery, it’s likely over-diluted. Gradually add more undiluted soap to balance consistency.
Improper storage can lead to spoilage. Liquid soap must be kept in airtight containers, away from light and moisture to prevent mould or bacterial growth. Opt for amber glass bottles with pump dispensers.
Mixing soap with incompatible products, like acidic cleaners, can destabilise its pH, ruining its texture or cleaning ability. Stick to water or soap-compatible additives like glycerin or essential oils. Test small batches when experimenting to ensure compatibility.
Frequently Asked Questions
How do you dilute castile soap for body wash?
To dilute castile soap for body wash, use one part castile soap to two parts water. For a standard 250ml bottle, mix 80ml of castile soap with 160ml of distilled or filtered water. If you prefer a thicker consistency, add ½ teaspoon of vegetable glycerin. For added fragrance, include 5–10 drops of essential oil such as lavender or tea tree. Shake gently to combine. Always test a small amount before using to ensure the dilution suits your skin. If you find it too drying, increase the water ratio slightly. Store the mixture in a clean, airtight bottle to prevent contamination.
Can I use castile soap as body wash every day?
Yes, you can use castile soap daily, but how your skin responds depends on your skin type. Castile soap is gentle and free from harsh detergents, making it ideal for sensitive skin. For dry skin, mix it with a moisturising component like almond oil or glycerin. Oily or acne-prone skin benefits from the soap's natural cleansing properties without stripping essential oils. However, if your skin feels tight or dry with daily use, try diluting the soap more or alternate usage with a richer, moisturising body wash. Pay attention to your skin’s needs and adjust accordingly.
What's the best dilution ratio for castile soap body wash?
The ideal dilution ratio depends on your preferences and how your skin reacts. A 1:2 ratio (one part castile soap, two parts water) is a good starting point for a gentle yet effective body wash. For ultra-sensitive skin, try a 1:3 ratio. If you want a more concentrated wash for particularly dirty or oily skin, a 1:1 ratio can work, though it may feel more drying for some. Always customise based on your needs, and test small batches before committing to a full bottle. Remember, adding a few drops of essential oil or glycerin can enhance the formulation.
Does castile soap dry out your skin?
Castile soap is generally gentler than many traditional soaps because it’s based on plant oils and doesn’t rely on some of the stronger synthetic surfactants found in conventional body washes. However, it’s still a true soap with an alkaline pH, so some people – especially those with very dry or barrier-impaired skin – may find it drying if it’s used too strong or too often. You can reduce this risk by diluting it well and enriching your mix with humectants and emollients such as glycerin, jojoba oil or aloe vera. Studies on glycerin-based moisturisers and recent work on jojoba’s effects on skin hydration and inflammation suggest that combining humectants and light oils can meaningfully improve hydration and barrier comfort when used alongside gentle cleansing. If your skin still feels tight or itchy after showering, dilute more, use a smaller amount, or alternate with a richer, non-soap cleanser.
How long does homemade castile body wash last?
Homemade castile body wash typically lasts 2–4 weeks if stored properly. Use an airtight bottle and keep it in a cool, dry place away from sunlight to prevent bacterial growth and deterioration. Adding a natural preservative, like 1% vitamin E or grapefruit seed extract, can extend its shelf life up to 6 months. Always use clean, sterilised containers, and avoid introducing water into the bottle during use, as this can shorten its lifespan. If the mixture changes colour, separates, or develops an odd smell, discard it immediately. Make small batches to ensure freshness.
Making your own Castile soap body wash is a satisfying way to embrace natural skincare while keeping a close eye on what touches your skin. With a simple base of plant oils and water, plus small additions of humectants, oils and botanicals, you can tailor your wash to different seasons, skin types and scent preferences. If you’d like ready-made options to sit alongside your DIY experiments, you can explore our Castile and olive-oil soap collection or browse our wider natural soap and skincare blog for more ideas, recipes and routines.
At The Humble Shepherd Co., we’re passionate about products that are kind to both skin and planet, from solid bars to liquid washes. If you’d like to be first to hear about new Castile-based releases and seasonal blends, you can also join our Shop Now waitlist and get a heads-up when fresh batches are ready. Whether you choose to mix your own, pick up a handmade bar, or do a bit of both, Castile soap is a versatile ally for building a cleaner, calmer, more sustainable bathroom routine.
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