We often say healthy locks start at the scalp, as caring for your precious hair follicles can help your mane thrive. But it actually starts even before that: It really starts with what nutrients you are feeding your body. Of course having a robust diet with a plethora of good-for-you foods is important for many reasons, many of which are far more important than your hair health. But having a full, lush head of hair as a result of a balanced diet? Well, that's not such a bad side effect either. 

So if you want to encourage healthy hair growth, here are some of the top nutrients to prioritize in your diet. (Here, we should also say that hair growth requires proper care from multiple angles—check out our full guide to hair growth here.) Read on and eat up: 

Your hair is made of the protein keratin. Keratin, like all proteins, is made up of a unique blend of amino acids—primarily cysteine, proline, and glycine. To get your fill of protein and amino acids, you'll want to consume things like poultry, lean meat, and fish (if you consume animal products), as well as chickpeas, lentils, oats, and beans (for the vegetarian and vegans among us). 

You can also supplement various protein support products, such as collagen supplements. While hair does not contain collagen (like the skin does), collagen peptides can provide your diet with more amino acids. Those amino acids can then be turned into keratin to form healthy hair at the follicle.* Additionally it can support scalp health and buffer against follicle irritation.* If you are looking for recommendations, check out our all-time favorite collagen supplements here. 

B vitamins, like biotin and niacin, can help support hair growth by supporting cellular energy production and tending to free radicals and encouraging healthy hair growth.* Biotin, in particular, seems to help with keratin production.* In one small study, women reported hair growth when supplementing with biotin (as part of a multi-ingredient supplement) when compared to those given a placebo.* Additionally, deficiencies are connected to loss and breakage.* However, biotin deficiency in the U.S. population is rare.

You can up your biotin intake via meat (especially organ meat), fish, eggs, seeds, nuts, and certain vegetables (sweet potatoes, broccoli, and spinach), as well as supplementation. 

Yes, even the sunshine supplement is linked to healthy hair. Vitamin D is thought to be one of the fat-soluble vitamins needed for creating and supporting functioning hair follicles.* Additionally, research shows that people who have low vitamin D levels may experience hair shedding as a result.* (Almost all Americans are failing to consume just 400 IU of vitamin D from their daily diet, and clinical vitamin D insufficiency persists in almost half of the population—41%, to be exact.) Additional research is needed to determine the vitamin's role in growth, but it's pretty apparent that not having enough can have an impact on normal hair health overall.* 

A few foods naturally contain vitamin D, such as shiitake and button mushrooms, mackerel, sockeye salmon, cod liver oil, sardines, and eggs—but consuming them in high enough quantities to meet your nutritional requirements is challenging. Thus, vitamin D supplements tend to be a key tool for most.* (Here's a list of our favorites!)

This list is non-exhaustive, of course, so be sure to check out our full list of vitamins and nutrients to support healthy hair. But if we had to pick just three? These essential players earn the top spots.