Prince Harry, 38, was pictured with thick, dark locks in a BetterUp advertising photo earlier this week.
However, just days previously at a polo match in Singapore, his flame-coloured mane was seen to be considerably thinner and lighter.
Spencer Stevenson, the founder of SpexHair, a leading hair loss and hair transplant adviser claimed the Duke of Sussex’s full head of hair might be “spray on hair”.
Mr Stevenson opined to The Sun: “I think it’s very likely he is using Nanogen hair fibres. This is an A-list celeb secret and helps many when they need to thicken their hair up instantly for a photo shoot or a movie.”
Nanogen Fibre Spray costs just £20 from Boots and it has the following description: “Perfect for men and women looking to improve the appearance of their hair.
“Nanogen hair thickening fibres are made of high quality, 100 percent natural keratin, a fibrous protein found in hair strands.
“Our fibres look more natural than others e.g. rayon, nylon and cellulose, and merge with your own hair making it visibly thicker and fuller.
“Available in 10 natural shades. Mix and match for highlights or a more vibrant colour.”
Mr Stevenson added: “I think Harry’s hair shows signs of being helped as it looks darker and thicker.”
Although the Prince would be very attractive whether he went bald or tried having long hair, specialists expect that Harry’s hair thinning will increase, a problem that most middle-aged men face.
Even A-list celebrities like Wayne Rooney, Gordon Ramsay, and David Beckham have had receding hairlines in recent years.
Nearly seven million Britons suffer from baldness or hair loss. According to the NHS, hair loss is “not usually anything to be worried about”.
It can be brought on by things like stress, sickness, weight loss, or iron deficiency. The majority of male midlife hair loss is simply hormonal.
Mr Stevenson commented: “Harry has experienced a significant amount of hair loss as a result of male pattern baldness.”
Prince William‘s hair loss was brutally referred to as “alarming” by Harry in his contentious memoir Spare.
However, the Prince of Wales appeared to embrace his baldness by spending £180 on a Numer One Buzz Cut in 2018.
Harry, on the other hand, seems to be putting a lot of effort into maintaining his full ginger head of hair.