My Stocks and Shares ISA and Self-Invested Personal Pension (SIPP) portfolios have started 2026 strongly. Some holdings are up by double digits, which is a pleasant surprise.
Let’s take a closer look at what’s going on, and why one FTSE 100 stock has started to make me uneasy.
Big portfolio moves
One strong stock market trade at the start of 2026 has been artificial intelligence (AI). Rising AI-led demand is creating a shortage in memory chips, pushing up prices.
I don’t own any of these memory chip stocks, but my SIPP holding in leading chipmaker Taiwan Semiconductor Manufacturing Company has risen 8.7%.
Meanwhile, my largest holding, MercadoLibre, has jumped 8.2%, largely off the back of Venezuela developments. It operates Latin America’s largest e-commerce marketplace, and could now theoretically re-enter Venezuela (if the government embraces capitalism).
Even one of my worst-ever stock picks — mRNA vaccine maker Moderna — has joined the party. It’s up 15% so far this year (though it’s still too deeply in the red for me).
Up 11%, BlackRock World Mining Trust continues to benefit from rocketing gold and copper prices, building on its 73% surge last year.
A newer position — premium sportswear brand On Holding — has increased 9%.
Booming defence shares
Another trend my portfolio’s benefitting from is a sharp rise in defence stocks. This has been sparked by events in Venezuela and elsewhere, with President Trump now calling for US military spending to rise massively to $1.5trn in 2027.
As such, BAE Systems and Rolls-Royce are up 19.7% and 10.3% respectively, year to date. BAE sources nearly half its revenue from the US.
My third-largest holding, Axon Enterprise, has also benefitted, rising almost 8% as it has some defence-related revenue.
A smaller holding — electric aircraft manufacturer Joby Aviation — could also benefit from higher military spending. It has a deal to supply the US Department of Defense with aircraft. As such, its stock has risen 15.5% in 2026.
I’m getting worried
While I’m happy with this start, I’m obviously not counting my chickens after just one week. AI and defence stocks could quickly pull back, and not all my shares are up (Roblox is down 10% and in freefall).
One holding from the FTSE 100 I’ve been worrying about is Coca-Cola HBC (LSE:CCH). The company makes and distributes Coca-Cola brands across multiple European and African countries, from “the West Coast of Ireland to the tropics of Nigeria“.
The stock has jumped 42% in the past 12 months, driven by solid operational performance.
So what’s my concern? Well, most of the company’s revenue comes from soft drinks, and I fear sales of these could increasingly be impacted by GLP-1 weight-loss drugs.
Multiple clinical studies show these treatments can reduce sweet cravings, which could theoretically include sugary drinks (and possibly even their taste, making them appear more metallic).
As daily Wegovy pills become cheaper and available to countless millions more people over the next decade, including in emerging markets, I worry this could hurt sales growth.
Admittedly, Coca-Cola HBC also sells water and coffee, and doesn’t have a large snacks business. The stock’s inexpensive. So I don’t see any immediate danger.
Still, I fear it could eventually suffer a similar fate to Diageo. As such, I’ll be keeping Coca-Cola HBC on a tight leash, while exploring other FTSE 100 opportunities.
