Jermain Defoe’s memory is almost as sharp as his two-footed shooting reflexes. “I know all my stats,” says the veteran Sunderland striker with 150 Premier League goals on the clock. “And I could probably tell you about every time I’ve scored.

“I remember my 100th goal in this division, it was for Tottenham against West Brom, outside of the box, right foot. And the first was against Ipswich for West Ham, Michael Carrick flicked it on and I finished at the near post. In terms of technique the best was probably my volley against Newcastle for Sunderland.”

It is no exaggeration to say the 34-year-old is obsessed with scoring and, having reached the 150 mark against Hull last Saturday, he seems determined to go at least one better at Anfield on Saturday. That would take Defoe beyond Michael Owen, the former Liverpool striker with whom he is currently level pegging.

“Moving above Michael on to 151 would be a good place to be,” he says. “Then my target would be to move closer to Robbie Fowler on 163. Then there’s Thierry Henry on 175 and Frank Lampard on 177.”

Placed in context – Defoe has never played for a truly leading team and is now at perennial relegation strugglers Sunderland – his record is extraordinary. So are the 18 Premier League goals he has registered in 2016, a tally topped only by Tottenham’s Harry Kane.

Self-sacrifice has played a big part. A bundle of creative energy in grey jeans and white T-shirt, he radiates health and could make a fortune from promoting a personalised diet – if only it were not quite so abstemious. Defoe never touches alcohol, shuns chocolate, drinks daily spinach, kale and nettle smoothies and consumes countless kilos of grilled salmon and steamed vegetables.

Significant caffeine intake, in the form of coffee, is permitted only on match days – “if I had it every morning I wouldn’t get the same benefit” – otherwise the striker drinks nothing but oceans of still water and green tea.

Until Sunderland installed their own ice chamber Defoe also regularly paid £1,000 a time to have one transported to his house. Once it was parked outside he would spent three minutes inside in order to accelerate recovery.

“I just want to keep playing, I love football and I don’t feel like I’m 34,” Defoe says. “I don’t feel I’m getting older. It helps that the yoga guy who comes into Sunderland has taught me how to control my breathing. It means you’re never out of breath.”

Sometimes, though, even he feels it can all become a little introspective. “The diet’s all about hydration and electrolytes,” he explains. “Sometimes it gets on my nerves.” In such moments he succumbs to a rare “vice” and reaches for the bubble gum. “I go to the MetroCentre and there’s this shop with sweets everywhere,” he admits. “Big bubble gums, they’re sweet for about 10 seconds, then you have to spit them out. The lady there orders them in for me now. She has two big boxes waiting in the back.”

Shunning alcohol has arguably been his best decision. “I never drink,” he says. “I’ve never said this before but my dad used to drink a lot so that’s one of the reasons why.

“But I’m not an angel. There’s loads of things I do wrong – I think people will have read about them in the papers – but I do try to do the right things at the right time.”

Accordingly last Saturday night he could be found at home sipping green tea with his mum and assorted other relatives as they saw him score against Hull City on Match of the Day. “Then I watched it again the next morning, then Goals on Sunday and Match of the Day 2,” he says.

It seems a shame Defoe does not have any major medals to complement his efforts. “Maybe one day,” he contemplates. “Who knows? I could win a cup at Sunderland. But no one can take the goals I’ve scored away from me.” Nor could they take his 55 England caps. “I have no message for Gareth Southgate,” says a man who does not anticipate adding to that collection. “I don’t need to say I should be in the England squad. It would be nice to be but I don’t know if it’s based on merit.”

Defoe is happier raiding that formidable memory bank. “My favourite goal?” he muses. “That was probably my fifth against Wigan [for Spurs in a 9-1 win in 2009] because at the time I knew I was only the third player to score five in a Premier League game. I was quite emotional and straightaway I thought, ‘Andy Cole, Alan Shearer and now me.’

“I was just buzzing to get up to my box and see my mum.”